Unable to mount azure file share all of sudden after package upgrades, complaining cifs not supported by the system

Question

I recently upgraded some packages when I logged into my linux vm. Then I tried to mount my file share, it complains "mount error: cifs filesystem not supported by the system. mount error(19): No such device".

I tried sudo dmesg | grep CIFS. no message regarding cifs.

I also checked my cifs installation it is the latest version. 2:6.14-1ubuntu0.1

My kernel is: 6.2.0-1016-azure

Can you help? I have large quantity of data on the file share now I can't access via linux vm and no computations can be done without them. Thank you

Answer 1

Hi Yun Chen, Welcome to Microsoft Q&A and Thanks for posting your query here!

This seems to be a known bug/issue for the kernel version linux-image-6.2.0-1016-azure.

Hence, either you can manually rollback to the previous kernel version following the below document:

https://learn.microsoft.com/en-us/troubleshoot/azure/virtual-machines/kernel-related-boot-issues#bootingup-differentkernel-ARVMManual

vi /etc/default/grub
GRUB_DEFAULT="1>2"

sudo update-grub

restart

Or the current workaround for new (i.e. no rollback kernel option) systems is to install the below module as cifs.ko is provided in the linux-modules-extra-azure module:

apt install -y linux-modules-extra-azure

Apparently the problem is that, between 6.2.0-1015 and 6.2.0-1016, the CIFS module was moved from fs/cifs/* to fs/smb/client/, fs/smb/common/ and fs/smb/server/*. The inclusion list (root/debian.azure-6.2/control.d/azure.inclusion-list) was not updated for this change, so the module is not included in the linux-modules-6.2.0-1026-azure package.

Reference Documents:

https://bugs.launchpad.net/ubuntu/+source/linux-azure/+bug/2042092

https://www.mail-archive.com/kernel-packages@lists.launchpad.net/msg514627.html

Please let us know if you have any further queries. I’m happy to assist you further.

Please do not forget to "Accept the answer” and “up-vote” whenever the information provided helps you, as this can be beneficial to other community members.

-Ekta