Administering SUSE Linux Enterprise Server for SAP applications Using Cockpit

1 About Cockpit #

Cockpit is a Web-based graphical interface that enables you to manage most administration tasks from one place. You do not need to create credentials for Cockpit as, by default, Cockpit uses the same credentials that you use to log in to your server. Cockpit uses APIs that already exist on the system without adding a layer to the system.

Cockpit enables you to perform the following tasks:

download container images and run containers
manage the server storage
inspect and change network settings
manage user accounts
view system logs
inspect and interact with systemd services
switch between SELinux modes
use a terminal on a remote server in your Web browser

2 Cockpit installation #

2.1 Installing Cockpit #

If Cockpit is not present on your system, you can install it by following the procedure below:

If the Cockpit instance is intended to serve as a primary one, you need to enable the Cockpit socket in systemd by running:
```
> sudo systemctl enable --now cockpit.socket
```
After running the command, the server exposes the default 9090 port and systemd starts the cockpit-ws service that listens on the 9090 port.

In case you have enabled the firewall, proceed as follows:

Open the firewall for Cockpit

> sudo firewall-cmd --add-service=cockpit --permanent && sudo firewall-cmd –reload

Restart cockpit.socket by running:

> sudo sudo zypper in -f cockpit-selinux-policies && sudo systemctl restart cockpit.socket

Now you can access the Cockpit Web interface by opening the following address in your Web browser:
```
https://IP_ADDRESS_OF_MACHINE:9090
```

2.2 Cockpit plug-ins #

Cockpit uses plug-ins to administer the system. The plug-ins are included in the installation pattern. However, depending on the technologies installed on your system, some plug-ins may not be visible to you. For example, if NFS is not present, the corresponding NFS panel is not visible.

3 Accessing Cockpit #

Cockpit enables you to log in directly to each machine that can expose the 9090 port. This machine is sometimes referred to as the primary server. It is the primary server that runs the cockpit-ws through which connections to additional servers are established. By default, Cockpit listens on both HTTP and HTTPS connections. However, most of the HTTP connections are redirected to HTTPS, with exceptions like local host access.

If the port cannot be accessed on the particular machine, you can still use Cockpit to administer the machine by using it as a secondary server. For the procedure of adding a server as secondary, refer to Procedure 2, “Adding a server as secondary”.

Note: A limited number of secondary servers

The number of secondary servers that you can administer from one primary server is limited to 20. If you need to administer more servers, add other primary servers or use another tool for cluster administration.

3.1 TLS certificates #

By default, Cockpit loads .cert or .crt certificates from the directory /etc/cockpit/ws-certs.d. The corresponding private key must be a separate file with the same file name but with the .key suffix. Make sure the key is not encrypted.

If no certificate is found in the directory, Cockpit generates a self-signed certificate (0-self-signed.cert) to establish a secure connection.

To check which certificate Cockpit uses, run the command:

> sudo /usr/libexec/cockpit-certificate-ensure --check

3.2 Authentication #

You do not need separate credentials to log in to Cockpit. Use the same credentials that you use to log in to SUSE Linux Enterprise Server for SAP applications. However, on new installations, login using root is not allowed by default. Either enable root login with a password as described in Section 3.2.2, “Enabling root to log in using a password”, or create an unprivileged user to access Cockpit. On instances upgraded from a previous release, root login is still allowed. In all cases, we recommend enhancing the security by adding 2FA as described in Section 3.2.1, “Enabling 2FA authorization”.

At first, you log in to Cockpit with limited access. To perform administrative tasks, click Limited access in the upper-right menu and unlock the administrative mode by entering your password.

3.2.1 Enabling 2FA authorization #

To set up 2FA on SUSE Linux Enterprise Server for SAP applications, you need an available TOTP application of your choice. Then run a command to configure the authorization. The following sections provide details on how to proceed with the configuration of 2FA and also give instructions in situations when your 2FA fails.

3.2.1.1 Applications providing TOTP 2FA #

The following applications providing 2FA are supported on SUSE Linux Enterprise Server for SAP applications.

Using cloud storage

PSONO - available for Firefox, Chrome, Docker, iOS, Android
Google Authenticator - available on Android, iOS and Wear OS
Okta Verify - available on Android, iOS, macOS and Windows

Using only local storage

Yubico Authenticator - with a hardware key
KeePassXC - available on Linux desktops, Windows and macOS
KeePassDX - available on Android
FreeOTP Plus - for Android
FreeOTP - for iOS

3.2.1.2 Setting up 2FA #

Each user can configure their own 2FA, or root can configure it for any regular user on the system. To set up 2FA for a user from a running system, proceed as follows.

Run the command:
```
> sudo /sbin/jeos-config otp
```
Scan the code to any TOTP application mentioned above.
Confirm the process by entering an OTP code.

3.2.1.3 Recovering access #

Setting up 2FA is optional. However, once set, the second factor is mandatory to log in to Cockpit. If the second factor becomes unavailable, you can change it or disable it. Even without the second factor, you can still log in to the machine using SSH or directly from a console. After login, you can use the following two options:

Change the second factor

Run the command either as root or with your user name using sudo:

> sudo /sbin/jeos-config otp

Disable the 2FA

Remove the file .pam_oath_usersfile from the affected user's home directory.

3.2.2 Enabling `root` to log in using a password #

Warning: root login with a password is not secure

We strongly discourage you from enabling root login with a password for security reasons.

In new SLES for SAP installations, root login using a password is disabled by default due to security reasons. To allow root login with password, proceed as follows:

Open the /etc/cockpit/disallowed-users file.
Remove root from the file.

3.3 Logging in to the primary server directly #

Whenever you have direct network access to the 9090 port, you can directly log in to the server using your credentials. To do so, follow Procedure 1, “Logging in to the primary server”.

Note: No dedicated credentials for Cockpit needed

By default, access is controlled by a Cockpit-specific PAM stack located at /usr/lib/pam.d/cockpit. The default configuration allows logging in with the same user names and passwords that are used for any local account on the system.

Procedure 1: Logging in to the primary server #

Go to the Cockpit login page by opening the following address in a browser:
```
https://IP_ADDRESS_OF_MACHINE:9090
```
Enter the credentials.

3.4 Logging in to secondary servers #

If your machine does not have direct access to the 9090 port, you can use this machine as a secondary server. Ensure that Cockpit is installed on the machine.

There are two ways of logging in to a secondary server: you can log in to a secondary server directly or you can use the primary server.

3.4.1 Logging in to secondary servers directly #

You can log in to any secondary server without logging in to the primary server first. This solution can be useful when you do not have credentials for the primary server. The primary server will be used as a bridge, and you will be connected to the secondary server using SSH.

To connect to the secondary server, proceed as follows:

Go to the Cockpit login page by opening the following address in a browser:
```
https://IP_ADDRESS_OF_MACHINE:9090
```
Fill in the credentials for the secondary server.
Expand Other options on the login screen.
Fill in the IP address of the secondary server.
Proceed by clicking Login.
If you are trying to log in for the first time, you are asked to verify the fingerprint. After this, click Accept and connect.

3.4.2 Accessing secondary servers from the primary server #

If you have credentials for the primary server, you can access secondary servers from the primary one. You must add the secondary servers first, as described in Procedure 2, “Adding a server as secondary”.

Procedure 2: Adding a server as secondary #

Log in to the primary server using the account with the system administrator role.
Click the USERNAME@HOSTNAME in the upper-left corner.
Click Add new host.
Fill in the host identification and optionally user name that will be used to log in to the server. You can assign a color to the machine. When the details are complete, click Add.
Verify the fingerprint on the server you want to add. If the fingerprint matches or if you have not set up the SSH connection, click Trust and add host to proceed.
Fill in the password and, if needed, check Automatic login. Cockpit will generate a new SSH key for the user, and next time you will be logged in automatically.

3.5 Switching to the administration mode #

By default, a regular user can log in to Cockpit with limited access that does not enable the user to perform administration tasks like managing user accounts, updating the system, and so on.

To switch to administrative access, proceed as follows:

Click the Limited access button.
Fill in the root password.
Click Authenticate to confirm.

To turn off administrative mode, proceed as follows:

Click Administrative access.
To confirm, click Limit access.

4 Configuring servers using Cockpit #

Using the Cockpit Overview part, you can perform changes to the default server configuration or the configuration you provided during the manual installation. In this part, you can change the host name or change the system date or time zone.

4.1 Viewing system health #

To view the system health, click Overview on the left pane. You can view the following details in the Health section.

If a service fails, you can click the 1 service failed to view the details of the service failure.

Click View login history to view your login history. You can modify the user credentials in the user page.

4.2 Viewing metrics and history #

You can view the PCP metrics and usage history under the Usage section in the Overview page.

Click Overview on the left pane.
The following details appear in the Metrics and History page.
CPU: The number of CPUs, the CPU load and a list of services that use the CPU.
Memory: The RAM and Swap memory usage, and the related services.
Disks: A list of used disks and partitions. Click View per-disk throughput to display a table showing the data transfer rates for each disk.
Network - Displays the list of networks.
Metrics history: When present, Cockpit integrates with the Performance Co-Pilot (PCP) framework to collect and manage system performance metrics. These metrics are used to render historical data visualizations on the Metrics and History interface. Cockpit can also use the archive logging subsystem of PCP to retrieve and display time-shifted historical data. In environments where PCP is not installed, Cockpit falls back to its own metrics collection mechanism; however, this mode does not support data archival or retrieval of historical metrics.
Archival of metrics depends on whether the pmlogger.service systemd unit is running or not. You can enable the Collect metrics option to enable and start the service.

4.3 Changing the server host name #

To change the host name, proceed as follows:

Procedure 3: Changing the host name #

Navigate to the Overview page.
In the Configuration section, click edit under Hostname.
Fill in the following:
- Pretty host name—a user-defined free-form host name
- Real host name—the name of the device in the network

4.4 Changing the system time or time zone #

To change the system time or time zone, proceed as follows:

Procedure 4: Changing system time or time zone #

Navigate to the Overview page.
In the Configuration section, click the current time value under System time.
In the pop-up window you can change the following:
- Time zone—the value set during the manual installation or, in case of raw images, set to UTC.
- Set time—by default, NTP is used for time synchronization. You can set the time manually or, if you defined alternative NTP servers, you can use those NTP servers for time synchronization.
- Click Change.

5 Filtering Cockpit logs #

Click Logs on the left navigation pane and select the required filters. You can filter the logs according to the following criteria:

Time. For details, refer to Section 5.1, “Filtering according to time”.
Priority. For details, refer to Section 5.2, “Filtering according to priority”.
Identifier. You can filter logs for a particular service, daemon or process. Available identifiers are parsed from the logs currently displayed according to the set filters.
Free-form filters. For details, refer to Section 5.3, “Logs filters”.

Note: The filter criteria are combined

When changing any of the time, priority or identifier criteria, the others are still applied. For example, if you change the time criterion to Last 24 hours, the priority and identifier criteria remain the same.

5.1 Filtering according to time #

To filter the logs according to a specific time, you can choose from the following values:

Current boot: Displays logs for the current boot only. The Resume button enables continuous refreshing of currently displayed logs.
Previous boot: Displays logs relevant to the previous boot.
Last 24 hours: Displays logs that were recorded within the last 24 hours.
Last 7 days: Displays logs that were recorded within the last 7 days.

5.2 Filtering according to priority #

The standard syslog severity levels are used (sorted from most to least severe):

Only emergency: The system is unusable. This is a panic condition.
Alert and above: This log requires your immediate action.
Critical and above: Failures in the primary systems. You should correct the problem immediately.
Error and above: Not an urgent error, but should be handled within a specific time.
Warning and above: Not an error, but indicates that an error might occur if no action is taken.
Notice and above: Unusual events that are not errors. No immediate action is required.
Info and above: Normal operational messages that serve as a confirmation that the system works properly.
Debug and above: These messages are used just for debugging the system.

5.3 Logs filters #

You can refine the logs view here according to the following criteria:

Since

Logs for the specified date or newer will be displayed. You can specify the time in the following way:

using the absolute date in the format YYYY-MM-DD
using any of the terms: yesterday, today, tomorrow and now
using relative time by prefixing the value with - or + and specifying units. You can use the following units: seconds or s, minutes or min, hours or h, days or d, weeks or w, months or m, and years or y.

Until

Logs for the specified date or older will be displayed. You can specify the time in the following way:

using the absolute date in the format YYYY-MM-DD
using any of the terms: yesterday, today, tomorrow and now
using relative time by prefixing the value with - or + and specifying units. You can use the following units: seconds or s, minutes or min, hours or h, days or d, weeks or w, months or m, and years or y.

Boot

Enter an integer: 0 means the current boot, -1 is for the previous boot, 1 for the first boot, 2 for the second, etc.

Unit

Specify the systemd unit for which you want to display logs. Use one of the formats:

_SYSTEMD_UNIT=NAME.service
COREDUMP_UNIT=NAME.service
UNIT=NAME.service

Free-form search

Enter the string that you want to find in the log messages. You can also use PERL-compatible regular expressions. Alternatively, you can filter messages according to message log fields in the format FIELD=VALUE. For example, CODE_LINE=349 displays logs with this value.

6 Managing storage using Cockpit #

The Storage page enables you to monitor traffic on your drives, repartition your system, manage NFS mounts, view storage logs, and create RAIDs or LVM.

6.1 Monitoring data flow on disks #

The graphs on the Storage page display reading and writing data flow to devices. Each device in the graph has a different color. Hover over the displayed data flow peak to identify the device name.

Graphs showing storage reading and writing spikes in Cockpit

Figure 1: Data flow view #

6.2 Managing file systems #

The Filesystems view enables you to create a partition table and to format or mount file systems. You can sort the mounted partition according to Name or Mount point.

6.2.1 Formatting partitions using Cockpit #

To format the partition, proceed as follows:

Procedure 5: Formatting partitions #

Navigate to the Storage page.
In the Filesystem view, click the partition you want to format.
Click Format next to the particular partition description to open the format window.
Enter a unique name for the partition.
In the Mount point, specify the directory to which the partition will be mounted. The Mount point field is mandatory.
In Type, select the file system type. Btrfs is mandatory for the / partition.
If needed, configure the encryption:
Passphrase and Confirm
Enter a passphrase to unlock the encrypted partition.
Store passphrase
The passphrase is stored in /etc/luks-keys and you are not asked for the passphrase on next boot.
Encryption options
You can pass a list of options described in supported encrypted options.
Select the Mount options. In the Custom mount options text field, you can enter a comma-separated list of options. For common options, refer to File system Independent Mount Options. These options are used in the options part of the /etc/fstab file.

6.2.2 Mounting partitions using Cockpit #

Note: The partition must be formatted

Before you try to mount a partition or disk, you need to format the device first. For details, refer to Procedure 5, “Formatting partitions”.

To mount a partition, proceed as follows:

Navigate to the Storage page.
In the Filesystems view, click the device to mount.
Click Mount to open the Mount filesystem window.
Specify the Mount point.
To select mount options in the Custom mount options text field, you can enter a comma-separated list of options. For common options, refer to File system Independent Mount Options. These options are used in the options part of the /etc/fstab file.
Select at which booting stage the partition must be mounted.
Click Mount to proceed.

6.3 Managing NFS mount points #

The NFS mounts view under the Storage page enables you to add, edit or delete NFS mounts.

6.3.1 Adding an NFS mount point #

To add an NFS mount point, proceed as follows:

Navigate to the Storage page.
From the three-line menu, select New NFS mounts view.
Specify the following values:
Server address
Provide the IP address or name of the NFS server.
Path on server
Select the available path on the NFS server that can be mounted.
Local mount point
Specify a directory on the local system where the path will be mounted.
Mount options
Check any of the options:
Mount at boot – to mount the path automatically after each start or restart of the system.
Mount read only – you will not be able to perform changes to the data on the NFS path.
Custom mount options is a comma-separated list of the mount command options.

6.3.2 Editing existing NFS mount points #

To edit an NFS mount, proceed as follows:

Navigate to the Storage page.
In the NFS mounts view, click on the particular NFS mount.
On the next screen, click Edit and specify the details described in NFS mount details.

6.4 Managing RAID using Cockpit #

Using Cockpit, you can create or modify software RAID of different levels.

6.4.1 Creating RAID using Cockpit #

Note: Sufficient number of disks

Make sure that you have enough disks available according to the RAID level.

To create a software RAID, proceed as follows:

Procedure 6: Creating a RAID #

Navigate to the Storage page.
Select the Create RAID device option in the three-line menu in the Devices view.
Enter the following parameters of the RAID:
Name
Enter a unique name for the RAID.
RAID level
Select one of the RAID levels.
Chunk size
The size of chunks in KBs. A chunk is the minimum amount of data read or written to each data disk in the array during a single read/write operation.
Disks
Select the disks that should be included in the RAID. The required number of disks depends on the selected RAID level.
Confirm the parameters by clicking Create. The RAID then appears in the Devices part.

6.4.2 Modifying RAID #

Using the Storage plug-in of Cockpit, you can stop or delete a RAID. Here you can also remove or add disks to the array.

To modify an existing RAID, proceed as follows:

Navigate to the Storage page.
Click the RAID in Devices to open the RAID details view.
In the detailed view, you can stop or delete the RAID, add or remove disks and format the device.
With certain RAID levels, you can switch on the Bitmap option that enables you to synchronize only the changes after a disk is temporarily disconnected. If the Bitmap is off, all data on the disk will be synchronized.

Note: Removing or adding disks

After any change in the disk number of the array, the system undergoes resynchronization that may take some time. Keep in mind that each RAID level requires a minimum number of disks. Therefore, Cockpit does not allow removing the disks that are required by the particular RAID level.

6.5 Managing volume groups and LVM #

6.5.1 Creating volume groups #

To create a volume group of disks, proceed as follows:

Click Storage.
Under the three-line menu in Devices, select Create LVM2 volume group.
Enter the volume group name.
Select the disks that will be part of the volume group.
Confirm the data with Create. The volume group appears in the Devices view.

6.5.2 Creating logical block volumes #

If you have a volume group, you can create a logical block volume from it. To do so, proceed as follows:

Navigate to the Storage page.
In the Devices, click the volume group you want to use.
Click Create new logical volume
Specify a logical volume name. Select a block device and choose the size to use.
Select the Block device for filesystems.
Select the size to use.
Click Create to confirm the details.
Format the block volume by clicking Format and filling the details as described in Step 4.

6.5.3 Creating a thin logical volume #

If you have a volume group, you can create a thin logical volume as described below:

Procedure 7: Creating a thin logical volume #

Navigate to the Storage page.
Click the volume group in Devices.
In the volume group details, click Create new logical volume.
Specify a logical volume name.
Select a pool of thinly provisioned volumes.
Select the size to use.
Click Create to confirm the details.
Create a thin volume by clicking Create thin volume.
Enter a unique name.
Select the size of the volume.
Click Create to confirm the thin volume.
You can create several volumes of the particular volume group by clicking Create thin volume again and repeating the steps above.
Format the volumes by clicking Format and filling the details as described in Step 4.

6.5.4 Managing logical volumes #

To perform any administration task on an existing logical volume, perform the following steps:

Navigate to the Storage page.
In the Filesystems view, click the logical volume.
Here you can perform the following actions with existing logical volumes:
Deactivate/Activate
In the three-dot menu, select Deactivate or Activate.
Mount
By clicking Mount and filling in the mount point and options, the volume will be mounted.
Shrink/Grow
The shrink/grow function is not available for all file systems.
In the expanded details about the volume, click Shrink or Grow.
Delete
In the three-dot menu, select Delete.

7 Managing networking using Cockpit #

After clicking Networking, you can view traffic on your system, manage the firewall, manage network interfaces, or view network logs.

7.1 Managing firewall rules and zones #

Cockpit enables you to create new zones or update the existing ones. In the firewall settings, you can add services to a zone or allow access to ports.

Note: Cockpit service is mandatory

Do not remove the Cockpit service from the default firewall zone as the Cockpit service may get blocked, and you may get disconnected from the server.

7.1.1 Adding firewall zones #

The public zone is the default firewall zone. To add a new zone, proceed as follows:

Procedure 8: Adding new firewall zones #

Navigate to the Networking page.
Click Edit rules and zones.
Click Add new zone.
Select Trust level. Each trust level of network connections has a predefined set of included services (the Cockpit service is included in all trust levels). The description for each trust level appears in the Description section.
Define allowed addresses within the zone. Select one of the values:
- Entire subnet to allow all addresses in the subnet.
- Range—a comma-separated list of IP addresses with the routing prefix, for example, 192.0.2.0/24, 2001:db8::/32.
Click Add zone.

7.1.2 Adding allowed services and ports to a zone #

You can add services to an existing firewall zone as described below:

Procedure 9: Adding services to a firewall zone #

Navigate to the Networking page.
Click Edit rules and zones.
Click Add services.
To add a service, select Services and choose the services from the list.
To allow custom ports, select Custom ports and specify the port value for UDP and/or TCP. You can assign an identifier to this port.
To confirm the changes, click Add services or Add ports, respectively.

7.2 About network bonds #

A bond interface is a combination of several network interfaces into one bond. Depending on the Mode (described further), network bonding can improve performance by increasing the network throughput and bandwidth. Network bonding can also increase fault tolerance by keeping overall connectivity even if some of the bonded interfaces stopped working.

7.2.1 Managing bonds #

7.2.1.1 Adding bonds #

Warning: Using DHCP when creating bonds may cause disconnection from Cockpit

When you try to create a network bond, you will be disconnected from Cockpit as its IP address changes if the following conditions are met:

DHCP is used on the server running Cockpit
the currently used network interface is added to the new network bond

To add a bond, proceed as follows:

Navigate to the Networking page.
Click Add bond.
Specify the following parameters of the bond interface:
Name
Enter a unique name for the interface.
Interfaces
Select which network interfaces should be grouped in the bond.
MAC
You can either select a specific MAC address of the underlying interface, or you can use any of the following options:
Permanent
Use the permanent hardware address if the device has a MAC address.
Preserve
During the bond activation, the MAC address is not changed.
Random
A random MAC address is created on each connection attempt.
Stable
Creates a hashed MAC address.
Mode
Keep the default mode or select any of the following modes:
Round Robin
Transfers packets from the first available interface to the last. The mode offers fault tolerance and load balancing.
Active Backup
Only one interface in the bonding is active. If the active interface fails, the backup will be activated.
XOR
Balancing using a transmit hash policy. The default is a modulo device count. To select a different policy, specify the xmit_hash_policy option in the Option field.
Broadcast
Everything is transmitted on all interfaces.
Adaptive Transmit Load Balancing
Channel bonding that does not require any special switch support. The outgoing traffic is distributed according to the current load on each interface.
Adaptive Load Balancing
Includes adaptive transmit load balancing and receive load balancing; no special switch support is required.
Primary
This selection is available only in the Active Backup mode. You can select a particular interface that will be used as primary, while other interfaces in the bond are used as secondary.
Link monitoring
Select the type of link monitoring.
Monitoring interval
Specifies the intervals at which the particular link monitor performs checks. The value is in ms.
Link up delay
Define the time in ms for how long the bond is disabled after a link has been activated. The value should be a multiple of the Monitoring interval value. Otherwise, it will be rounded to the nearest value. Available only for the MII link monitor.
Link down delay
Define the time in ms for how long the bond is disabled if a link failure has been detected. The value should be a multiple of the Monitoring interval value. Otherwise, it will be rounded to the nearest value. Available only for the MII link monitor.
Monitoring targets
Specify the list of host IP addresses that you want to monitor. Available only for the ARP link monitor.
Click Apply.

7.2.1.2 Modifying bonds #

To modify a bond, proceed as follows:

Navigate to the Networking page.
Click on the particular bond name to open the details.
You can modify the following bond parameters:
Bond
Click the bond name and the bond details appear. Modify the details and click Save.
Connect automatically
The bond connects automatically by default. Clear the box to disable the automatic connection.
IPv4 and IPv6
After clicking edit, you can set an IP address and configure a specific DNS, DNS search domain and routes.
MTU
By default, Automatic is selected. After clicking edit, you can specify a particular value of the maximum transmission unit in bytes or select Automatic.
Bond
After clicking edit, you can edit the same parameters as when you were creating the bond interface.

7.3 Managing network bridges #

A network bridge is a device that creates a single aggregated network from multiple networks.

7.3.1 Creating network bridges #

Warning: Using DHCP when creating network bridges may cause disconnection from Cockpit

When you try to create a network bridge, you will be disconnected from Cockpit as its IP address changes if the following conditions are met:

DHCP is used on the server running Cockpit
the currently used network interface is added to the new network bridge

To create a network bridge, proceed as follows:

Navigate to the Networking page.
In the Interfaces view, click Add bridge.
Specify the following:
Name
Specify a unique name for the bridge.
Ports
Select the interfaces to be included in the bridge.
Spanning Tree Protocol (STP)
STP is a network protocol used for Ethernet networks that prevents bridge loops by setting a preferred link whenever network switches are connected with several links. This preferred link is used for all Ethernet traffic unless it fails. In that case, a redundant link is used instead. For details regarding STP, see STP.
If you enable the STP protocol, you can edit the following settings:
STP priority
The lower the priority, the higher the probability of the switch becoming the root switch.
STP forward delay
Specify the time spent in the listening and learning state (in seconds). The default value is 15 s, but you can use any value between 4 and 30 s.
STP hello time
Specify the time between each bridge protocol data unit (BDPU) that is sent on a port (in seconds). The default value is 2 s, but the recommended range is 1 to 10 s.
STP maximum message age
Specify the maximum length of time that passes before a bridge port saves its configuration BPDU information.
Click Add

7.3.2 Modifying or deleting existing bridges #

To modify or delete a bridge, proceed as follows:

Navigate to the Networking page.
In the Interfaces view, click the bridge name to open the details.
To delete the bridge, click Delete.
To modify, change any of the following details and click Save.
General
The bridge connects automatically by default. To disable the automatic connection, uncheck the option.
IPv4 and IPv6
After clicking edit, you can set the IP address and configure a specific DNS, DNS search domain and routes.
Bridge
By clicking edit, you can edit all parameters of the bridge.

7.4 Managing VLANs using Cockpit #

A virtual local area network is a logical subnetwork that groups devices from different physical LANs.

7.4.1 Creating a virtual local area network #

To add a VLAN, proceed as follows:

Navigate to the Networking page.
In the Interfaces view, click Add VLAN.
Fill in the VLAN details:
Parent
Select the parent network interface.
VLAN ID
Specify an ID in the range 1–4094.
Name
Enter the name of the VLAN.
Click Add VLAN.

7.4.2 Modifying or deleting existing VLANs #

To modify or delete an existing VLAN, proceed as follows:

Navigate to the Networking page.
In the Interface view, click the VLAN name.
To delete the VLAN, click Delete or modify any of the following details and click Save.
Parent
Select the parent network interface.
VLAN ID
Specify an ID in the range 1–4094.
Name
Enter the name of the VLAN.

8 Working with containers #

After the first login to Cockpit, you need to start Podman. Keep the default check box selected to start Podman automatically on each boot.

The Podman containers page enables you to pull images from registries and manage your containers. You can also filter the view by entering a filter criterion into the filter field.

8.1 Managing container images #

Note: openSUSE registry and Docker Hub not enabled by default

The openSUSE registry and Docker Hub are not configured in the default installation. To download container images from those registries, you need to add the registries to the /etc/containers/registries.conf file as follows:

unqualified-search-registries = ["registry.suse.com", "registry.opensuse.org", "docker.io"]

In the Images view, you can download, update or delete already pulled images. Each function is available through the three-dot menu. After clicking the menu, there are the following options:

Download new image: How to proceed with downloading an image is described in Procedure 10, “Downloading a new image”.
Pull all images: Cockpit pulls new versions of the container images you already downloaded.
Prune all unused images: All images that are not used by any container will be removed.

Procedure 10: Downloading a new image #

In the Podman containers › Images view, open the three-dot menu and select Download new image.
Select the Owner to define who can see the downloaded image. The System restricts the image visibility to users with administrative access. The image downloaded under the User owner is visible to the regular user and also to all other users with administrative access.
Choose a preferred image registry or proceed with All registries.
Define the Tag. The default value is latest.
Fill in the image name or description in the Search for field to start the search.
Cockpit suggests possible images according to the entered name, registry and tag.
Select the desired image and click Download.

8.2 Managing containers using Cockpit #

8.2.1 Running new containers from images #

Note: Image required to run a container

To run a container, you need a container image. The image can be pulled using Podman or Cockpit. When using Cockpit, you can pull an image in advance as described in Procedure 10, “Downloading a new image”, or you can pull the image directly from the Create container form as described below.

To run a new container, proceed as follows:

Navigate to the Podman containers page.
If you pulled an image in advance:
1. In the Images view, click Show images.
2. Click Create container next to the image you want to use.
If you do not have the image, click Create container in the Containers view.
In the Create container window, enter the container details as described below. Note that some options are available only for system administrators.
In the Details tab, enter the following details:
Owner
Select whether the container will be visible only for users with sudo privileges by selecting system. The user defines that the container is visible to privileged users and regular users.
Name
Specify a unique name for the container.
Image
This field is enabled if you do not have an image. After you start typing the image name, Cockpit makes suggestions of images in the configured registries.
Pull the latest image
The checkbox is available if you are creating the container from an already downloaded image. If selected, the latest image version is pulled before the container is started.
Command
You can specify a command to run in the container.
With terminal
Select the option to gain access to the container using a terminal. If not selected, the container will be in the detached state.
Memory limit
You can limit the maximum memory consumption of the container by checking the box and specifying the limit.
CPU shares
Specify the weight of the container to use CPU time. The default weight is 1024. The weight applies only if containers are under high load. If the tasks in one container are idle, other containers may use its CPU time.
If you have four containers, two of them have CPU shares of 512 and the other two have 1024. Thus, under high load, the containers with lower CPU shares get only 16,5% of CPU time, while those with 1024 CPU shares get 33% of CPU time.
In the Integration tab, you can enter the following parameters:
Port mapping
After you click the Add port mapping button, specify the host IP address, the host port to map the container port onto, the container port and select the protocol. If you do not set the host IP address or set the value to 0.0.0.0, the port is bound to ALL host IP addresses. If you omit the host port, a random one is used for the mapping.
Volumes
This field maps a path in a container onto a path on the host machine. Fill in the host path, the container path and select the SELinux label.
The SELinux label private defines that the volume is accessible only from the particular container. The shared label means that all containers can access the volume.
Environment variables
To define environment variables in the container, click Add variable and fill in Key and Value. You can enter multiple variables by adding more lines.
In the Health check tab, you can set the interval for triggering commands to check the container's status. Fill in the following parameters:
Command
Specify the command that is triggered to check the container status.
Interval
Specify the interval of checks in seconds.
Timeout
The maximum time in seconds to wait before the interval is considered failed.
Start period
The time interval after the container is started when the health check is not performed.
Retries
Specify how many times the check can be performed before the status is considered unhealthy.
When unhealthy
Select the action to take after a container is considered unhealthy.
To create the container, click Create or Create and run to create and start the container.

8.2.2 Further actions with running containers #

Under the three-dot menu, you can perform the following actions:

delete the container
pause the container
commit changes performed to the container, for example, installing packages to the container
checkpoint the container—write the state of the container to disk and stop the container
restart the container either by regular Restart, where processes running inside the container are stopped, or by Force restart, where the processes are killed, and you may lose data
stop the container, either by regular Stop, Force stop or Checkpoint. When using Checkpoint, the state of all processes in the container is written to the disk, and after the next start, the container is restored to the same point before stopping.

By expanding the container details, you can access the container's terminal in the Console tab and view its information in other tabs.

8.3 Pods management #

8.3.1 Creating pods #

Cockpit enables you to create pods in which you can then create containers. To create a pod, follow the steps:

Navigate to the Podman containers page.
Click Create pod.
Fill in the pod details:
Name
Enter a unique name for the pod.
Owner
Specify whether the pod will be visible only under root privileges or also to regular users.
Port mapping
After clicking Add port mapping, you can map a pod port onto a host port. Specify the container's port, assign the desired host port and IP address. If the host IP address is not set or is set to 0.0.0.0, the port is bonded to all host IP addresses. If you omit the host port number, a random port number is assigned to the mapping.
Volumes
After clicking Add volume, you can map a directory on the host onto the container's volume. Select the host path, enter the path in containers and select the SELinux labeling.
Click Create to confirm the pod creation.

8.3.2 Creating containers in pods #

Important: Existing containers cannot be added to pods

During the planning, note that only new containers can be run in a pod. You cannot add an already created container that has not been run under a pod to any pod.

To create containers in a pod, follow the steps:

Navigate to the Podman containers page.
In the desired pod group, click Create container in pod.
Fill in the container details as described in Section 8.2.1, “Running new containers from images”. Remember that the owner of new containers is the same as the owner of the particular pod.

9 User administration using Cockpit #

The Cockpit Accounts screen enables you to administer user accounts and groups. You can search and view the users, manage the user access and delete users.

Note: User administration only for server administrators

Only users with Administrative access can edit other users.

Using the Accounts Cockpit screen, you can perform the following tasks:

Creating new users of the system as described in Section 9.2, “Creating user accounts using Cockpit”
Assigning sudo privileges to user accounts as described in Section 9.1, “Modifying existing user accounts”
Forcing a change of a user's password as described in Section 9.1, “Modifying existing user accounts”
Locking a particular user account as described in Section 9.1, “Modifying existing user accounts”

9.1 Modifying existing user accounts #

To modify a user account, proceed as follows:

Navigate to the Accounts page.
Click the account you want to modify.
In the user details view, you can perform the following actions:
Delete the user
Click Delete to remove the user from the system.
Terminate user's session
By clicking Terminate session, you can log a particular user out of the system.
Manage access to the account
You can set a date for when the account will expire. The default is to never expire.
You can disallow the user to use their password to log in. The user then must use a different method of authentication.
Manage the user's password
Click Set password to set a new password for the account.
By clicking Force change, the user will have to change the password on the next login.
Click edit to set whether and when the password expires.
Add SSH key
You can add an SSH key for passwordless authentication via SSH. Click Add key, paste the contents of the public SSH key and confirm it by clicking Add.
Change shell
Click the shell name and select the shell from the list.
View login history
You can view the login history of the user.

9.2 Creating user accounts using Cockpit #

To add a new user to the system, proceed as follows:

Navigate to the Accounts page.
Click Create new account to open the window that enables you to add a new user.
Fill in the user account details. You can assign a different home directory to the user in the Home directory text box. If you do not specify a directory, the standard /home/USERNAME path is used.
If you select Disallow password authentication, the user will have to use an authentication method other than filling in a password, for example, an SSH login.
Click Create to confirm the account.
To add an SSH key to the account, you need to modify the account as described in Section 9.1, “Modifying existing user accounts”.

9.3 Creating user groups #

The topic covers the creation of user groups.

To create a user group, proceed as follows:

Navigate to the Accounts page.
Click Create new group.
Enter a unique name for the group and specify or leave the default ID.
Note
The already existing group ID cannot be overwritten. Group IDs under 1000 are usually reserved for system accounts, services, and so on. If you create a group with an ID less than 1000, the group cannot be later deleted using Cockpit.

10 Managing services using Cockpit #

The following sections describe how to start, stop and restart a service, target, socket, timer or path.

10.1 Managing `systemd` units #

To manage a systemd unit, proceed as follows:

Click the Services page.
Select the appropriate tab (System services, Targets, Sockets, Timers or Paths).
Click the unit you want to administer.
In the unit details, you can view relations to other systemd units, the status of the unit, or you can perform the following actions that can be found in the three-dot menu:
- Start if the unit is not running
- Restart the running unit
- Stop the running unit
- Disallow running—that will stop the service permanently, including all its dependencies. Keep in mind that the dependent service can be used by other units, and disallowing the unit may cause serious trouble for the system.

10.2 Creating new timers #

systemd timers help you in automating recurring tasks. A systemd timer can control the triggering of systemd services and the handling of events.

Note: Overriding existing timers

The default set of systemd timers is stored in /usr/lib/systemd. If you create a timer with already existing names, the default unit file is not overwritten, but a new one is created in /etc/systemd/system/ that overrides the default unit file. To restore the timer to the default one, delete the timer unit file in /etc/systemd/system/.

If you try to create a timer that already exists in the /etc/systemd/system/ directory, the unit file will be overwritten, and the previous changes are lost.

To create a systemd timer using Cockpit, proceed as follows:

Navigate to Services.
In the Timers tab, click Create timer.
Fill in the details:
Name
The name of the timer that will be used in the unit name and in the service unit name as well. For example, specifying the name example will create the following unit files: /etc/systemd/system/example.timer and /etc/systemd/system/example.service.
Description
You can provide a short description of the timer.
Command
The command to be invoked when the timer is triggered.
Trigger
The timer can be triggered each time you reboot your machine or at a specific time. For the After system boot option, you can define the delay of the service invocation. For the At specific time option, specify when the service should be invoked.
Click Save.

11 Managing Subscriptions using Cockpit #

Cockpit enables you to register new subscriptions, view the list of registered and available subscriptions and also deregister subscriptions.

11.1 Register new subscription #

To register a new subscription, you must have a registration code and an e-mail address.

Navigate to the Subscriptions section.
In the Register a new subscription section, enter the details as described below.
Registration code
Specify the registration code.
Email
Specify the e-mail address.
Click Register.

11.2 Edit subscription settings #

You can edit the subscription settings.

Navigate to the Subscriptions section.
Click Edit Settings.
Specify the proxy URI.
To allow insecure proxy addresses, select the Allow insecure Proxies check box.
Select the language code in Language.
Click Save.

11.3 Register available extension #

Extensions that you can use are listed under Available Extensions. To register an extension, proceed as follows:

Navigate to the Subscriptions section.
In the Available Extensions section, click Register corresponding to the extension you want to register.

11.4 Deregistering subscriptions or extensions #

You can deregister subscriptions or extensions using Cockpit.

Navigate to the Subscriptions section.
In the Registered Subscriptions section, click De-register corresponding to the subscription or extension you want to deregister.

12 SELinux mode and policy #

The SELinux tool enables you to switch between SELinux modes and view current modifications of the SELinux policy.

Important: Missing SELinux module

The SELinux Cockpit module is visible only if SELinux is enabled on the system. If you cannot access the module, SELinux is probably disabled. To check that SELinux is enabled, run:

> sestatus

On SUSE Linux Enterprise Server for SAP applications, SELinux is in the enforcing mode by default. To temporarily switch to the permissive mode, click the button with the Enforcing label. Note that the change persists only until the next boot. If you need to perform a persistent change of the mode, edit the configuration file /etc/selinux/config.

The System modifications lists all modifications performed on the default SELinux policy. If you want to export the modifications and reuse them on different servers, click View automation script. In the new window, you can copy a shell script or an Ansible configuration file that can be applied on other servers.

12.1 Updating SLES for SAP using Cockpit #

To update your system, proceed as follows:

Navigate to the Software updates page.
Click the Check for Updates icon to get a list of new package updates and patches available for your system. We recommend installing the patches marked as important as soon as possible.
Now you can update your system either with immediate reboot, or the reboot might be postponed:
1. Click Install all updates to install all updates. By default, all available updates are selected.
  To install specific updates, select Unselect all and then select the required updates and click Install selected updates.
  After the installation is complete, you can reboot your system or click Ignore to postpone the reboot.
  Note
  When the Web Console is restarted, you will no longer see progress information. However, the update process will continue in the background. Reconnect to continue watching the update process.
2. To reboot the system after installation, enable the Reboot after completion toggle button. By default, the Reboot after completion toggle button is disabled. You must reboot the system to activate the snapshot with updates. If you perform further changes without rebooting the system beforehand, a new snapshot will be created from the same point as the snapshots with updates. Therefore, the new snapshot will not include the updates.
3. To view the installed package information, click Package information.
4. In the Reboot window, enter the message for the logged-in users and select the time delay for the reboot.
5. Click Reboot.
You can view the update history in the Update history section.

12.2 Managing Software Repositories using Cockpit #

Cockpit enables you to view, add, edit, and delete software repositories.

12.2.1 Adding new repository #

To add a new repository, you must have the repository URL.

Navigate to the Software Repositories section.
Click Add repo.
In the Add repo window, enter the repository details as described below.
Alias
Specify the repository alias.
Name
Specify a unique name for the repository.
Priority
Specify the priority number. The default priority is set to 99.
You can set the priority within the range 1 to 99. Where 99 denotes lowest priority and 1 the highest.
Enabled
The check box is enabled by default. To disable the repository, clear the check box.
Autorefresh
The check box is enabled by default. To disable auto-refresh for the repository, clear the check box.
GPG Check
The check box is enabled by default. To disable the GPG Check, clear the check box.
Uri
Specify the repository URI.
Click Save.

12.2.2 Refreshing repositories #

You can refresh repositories manually.

Navigate to the Software Repositories section.
Click Refresh repositories.
The repositories are refreshed, and a window appears stating that the repos refresh is successful.
Click Ok

12.2.3 Editing repositories #

You can edit repositories. You cannot edit the repository URI using Cockpit.

Navigate to the Software Repositories section.
Click the three-dot menu and click Edit.
Modify the required details and click Save.

12.2.4 Deleting repositories #

You can delete repositories using Cockpit.

Navigate to the Software Repositories section.
Click the three-dot menu and click Delete.
Click Delete to confirm deletion.

12.3 Solving SELinux access issues #

In the SELinux page, you can view access denial messages from the audit log. On top of that, Cockpit provides possible ways of solving the access denial. To do so, follow the steps:

Navigate to the SELinux page.
In SELinux access control errors, expand the details regarding access denial.
To view the audit log record, click Audit log.
To view possible solutions, click Solutions. Some solutions may be applied directly through Cockpit by clicking Apply this solution.

13 Legal Notice #

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or (at your option) version 1.3; with the Invariant Section being this copyright notice and license. A copy of the license version 1.2 is included in the section entitled “GNU Free Documentation License”.

For SUSE trademarks, see https://www.suse.com/company/legal/. All other third-party trademarks are the property of their respective owners. Trademark symbols (®, ™ etc.) denote trademarks of SUSE and its affiliates. Asterisks (*) denote third-party trademarks.

All information found in this book has been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. Neither SUSE LLC, its affiliates, the authors, nor the translators shall be held liable for possible errors or the consequences thereof.