Recovering the Cloud Backup agent after a Linux kernel update

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Updated at July 29, 2026

Updating the Linux kernel on a resource connected to Cloud Backup may affect the performance of the Cloud Backup agent: it will not be able to create a backup of the resource or recover it from a backup.

This may affect the agent’s performance, since the SnapAPI module (developed by the backup provider for the agent to work with disks and built by the DKMS framework for a specific Linux kernel) may not update after updating the kernel and may therefore cease to match the kernel version.

To restore the Cloud Backup agent’s performance affected by a Linux kernel update, you need to update the version of the Linux kernel headers DKMS refers to when building the SnapAPI module. Once the kernel header version matches the kernel version, DKMS will rebuild the SnapAPI module for the required Linux kernel version at the next start of the resource.

Debian/Ubuntu

CentOS

Make sure the Linux kernel version does not match that of the kernel headers:
- To find out the Linux kernel version, run this command in the terminal:
```
uname -r
```
  Result:
```
6.1.0-31-amd64
```
- To find out the version of the Linux kernel headers, run this command:
```
sudo apt list --installed | grep header
```
  Result:
```
linux-headers-6.1.0-27-amd64/stable,now 6.1.115-1 amd64 [installed]
linux-headers-6.1.0-27-common/stable,now 6.1.115-1 all [installed,automatic]
```
As you can see from the command outputs, the versions are different: the Linux kernel version is 6.1.0-31, and the Linux kernel header version is 6.1.0-27.
Install the linux-headers package for the new Linux kernel:
```
sudo apt install linux-headers-$(uname -r)
```

Make sure the new kernel headers have been added:

sudo apt list --installed | grep header

Result:

linux-headers-6.1.0-27-amd64/stable,now 6.1.115-1 amd64 [installed]
linux-headers-6.1.0-27-common/stable,now 6.1.115-1 all [installed,automatic]
linux-headers-6.1.0-31-amd64/stable-security,now 6.1.128-1 amd64 [installed]
linux-headers-6.1.0-31-common/stable-security,now 6.1.128-1 all [installed,automatic]

Reboot your OS:
```
sudo reboot
```
During the reboot, the DKMS framework will rebuild the SnapAPI module for the required Linux kernel version and the Cloud Backup agent will run.
If the Cloud Backup agent's performance is not restored after a reboot, complete the following steps to manually rebuild the SnapAPI kernel module for the required version:
1. Find out the Linux kernel version:
```
uname -r
```
  Result:
```
6.8.0-110-generic
```
  As you can see in the output, the Linux kernel version is 6.8.0-110-generic. You will need this value when updating the module.
2. Find out the SnapAPI version. If missing, install the dkms utility for your OS first:
```
sudo dkms status | grep snapapi
```
  Result:
```
snapapi26/2.0.6, 5.15.0-119-generic, x86_64: built
snapapi26/2.0.6, 6.8.0-48-generic, x86_64: built
```
  As you can see in the output, the SnapAPI module version is snapapi26/2.0.6. You will need this value when updating the module.
3. Update the SnapAPI module by populating the command with the SnapAPI and Linux kernel versions you obtained previously:
```
sudo dkms install snapapi26/2.0.6 -k 6.8.0-110-generic
```
  Result:
```
Building module:
cleaning build area...
...
- Installation
  - Installing to /lib/modules/6.8.0-110-generic/updates/dkms/
depmod.......
```
4. Run the command again to check the installed SnapAPI version:
```
sudo dkms status | grep snapapi
```
  Result:
```
snapapi26/2.0.6, 5.15.0-119-generic, x86_64: built
snapapi26/2.0.6, 6.8.0-110-generic, x86_64: installed
snapapi26/2.0.6, 6.8.0-48-generic, x86_64: built
```
5. Reboot your OS:
```
sudo reboot
```

Make sure the Linux kernel version does not match that of the kernel headers:
- To find out the Linux kernel version, run this command in the terminal:
```
uname -r
```
  Result:
```
3.10.0.1160.81.1.el7.x86_64
```
- To find out the version of the Linux kernel headers, run this command:
```
sudo yum list installed | grep kernel-dev*
```
  Result:
```
kernel-devel.x86_64             3.10.0-1160.76.1.el7            @updates
```
As you can see from the output of the commands, the versions are different: the Linux kernel version is 3.10.0.1160.81.1.el7, while the version of the Linux kernel headers is 3.10.0-1160.76.1.el7.
Install the linux-headers package for the new Linux kernel:
```
sudo yum install kernel-$(uname -r)
```

Make sure the new kernel headers have been added:

sudo yum list installed | grep kernel-dev*

Result:

kernel-devel.x86_64             3.10.0-1160.76.1.el7            @updates
kernel-devel.x86_64             3.10.0.1160.81.1.el7            @updates

Reboot your OS:
```
sudo reboot
```
During the reboot, the DKMS framework will rebuild the SnapAPI module for the required Linux kernel version and the Cloud Backup agent will run.
If the Cloud Backup agent's performance is not restored after a reboot, complete the following steps to manually rebuild the SnapAPI kernel module for the required version:
1. Find out the Linux kernel version:
```
uname -r
```
  Result:
```
6.8.0-110-generic
```
  As you can see in the output, the Linux kernel version is 6.8.0-110-generic. You will need this value when updating the module.
2. Find out the SnapAPI version. If missing, install the dkms utility for your OS first:
```
sudo dkms status | grep snapapi
```
  Result:
```
snapapi26/2.0.6, 5.15.0-119-generic, x86_64: built
snapapi26/2.0.6, 6.8.0-48-generic, x86_64: built
```
  As you can see in the output, the SnapAPI module version is snapapi26/2.0.6. You will need this value when updating the module.
3. Update the SnapAPI module by populating the command with the SnapAPI and Linux kernel versions you obtained previously:
```
sudo dkms install snapapi26/2.0.6 -k 6.8.0-110-generic
```
  Result:
```
Building module:
cleaning build area...
...
- Installation
  - Installing to /lib/modules/6.8.0-110-generic/updates/dkms/
depmod.......
```
4. Run the command again to check the installed SnapAPI version:
```
sudo dkms status | grep snapapi
```
  Result:
```
snapapi26/2.0.6, 5.15.0-119-generic, x86_64: built
snapapi26/2.0.6, 6.8.0-110-generic, x86_64: installed
snapapi26/2.0.6, 6.8.0-48-generic, x86_64: built
```
5. Reboot your OS:
```
sudo reboot
```

If you were unable to recover your Cloud Backup agent for any reason, contact support.

Recovering the Cloud Backup agent after a Linux kernel update

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