ceph tentacle and libvirt

[PPisz]

We upgraded Ceph to Tentacle, and everything went fine, but all hosts running Ubuntu 22 and 24 lost connectivity to RBD at the libvirt level. In Cloudstack, the hosts are in a disconnected state, and can't connect to the RBD pool. Has anyone experienced this?

I would be grateful for your help, we have a serious breakdown.

[DaanHoogland]

@PPisz , this looks like you are/were on you’re own. How are you doing?

[PPisz]

Hi dahn! It's okay, we managed to work around it. The cause of the crash was NFS (restart during a Ceph update). Libvirt was waiting for NFS and endlessly trying to mount secondary storage. This was causing the VMs to freeze because they had NFS-based config drives mounted. Mitigation was simple on one hand; restarting the host or ejecting the VM's config drive from the server was enough. However, the problem was serious because it affected the entire environment in an instant, halting 70% of virtualization. For now, we've switched from secondary storage to S3 and removed NFS from the environment as much as possible. Best regards, Piotr From: dahn ***@***.***> Sent: Tuesday, August 11, 2026 12:09 PM To: apache/cloudstack ***@***.***> Cc: Piotr Pisz ***@***.***>; Mention ***@***.***> Subject: Re: [apache/cloudstack] ceph tentacle and libvirt (Discussion #12620) @PPisz <https://github.com/PPisz> , this looks like you are/were on you’re own. How are you doing? — Reply to this email directly, view it on GitHub <#12620?email_source=notifications&email_token=AIWHLTF462LXDQK5NRWHFQ35JLWCPA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZZG42DGNBUUZZGKYLTN5XKO3LFNZ2GS33OUVSXMZLOOSWGM33PORSXEX3DNRUWG2Y#discussioncomment-17974344> , or unsubscribe <https://github.com/notifications/unsubscribe-auth/AIWHLTABRL5PMJGJOO55EDL5JLWCPAVCNFSNUABFKJSXA33TNF2G64TZHM4TONJZGQ2DQO2ENFZWG5LTONUW63R3HE2DKMJWGUYKC5QC> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/AIWHLTB77XASQ35NNIH7BV35JLWCPA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZZG42DGNBUUZZGKYLTN5XKO3LFNZ2GS33OUVSXMZLOOSVGM33PORSXEX3JN5ZQ> and Android <https://github.com/notifications/mobile/android/AIWHLTHPLPRCKYY6RWTTOD35JLWCPA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZZG42DGNBUUZZGKYLTN5XKO3LFNZ2GS33OUVSXMZLOOSXGM33PORSXEX3BNZSHE33JMQ> . Download it today! You are receiving this because you were mentioned. <https://github.com/notifications/beacon/AIWHLTD6CIUQ643UZUQSHUL5JLWCPBFCNFSM6AAAAAC5HS3YD6WGG33NNVSW45C7OR4XAZNRIRUXGY3VONZWS33OINXW23LFNZ2KUY3PNVWWK3TUL5UWJTQBCJCERJTSMVQXG33OU5WWK3TUNFXW4.gif> Message ID: ***@***.*** ***@***.***> >

[DaanHoogland]

thanks for the update @PPisz