OpenVZ7 can't snapshot/suspend a cPanel VE
I recently deployed a couple of new OVZ7 hostnodes, we are looking to transition from older OVZ to OVZ7. We have many cPanel servers on older OVZ hostnodes. To test OVZ7 I moved a cPanel server from old to new using the ovztransfer.sh script as per the documentation. The move seemed to go ok and the server worked, however I found that after it was moved I could not snapshot the container or perform any operation that requires the server to be snapped/checkpointed. I figured this was a one off problem and more than likely related to a botched move using the ovztransfer.sh script. So instead I decided to build an entirely new VE on the OVZ7 hostnode. A brand new Centos7 install with a new fresh install of the latest version of cPanel. After I had that VE up and running I migrated cPanel users from source server to new target server using typical cPanel migration (transfer tools). After the user data was migrated I attempted to snapshot/suspend the new container and it is again failing. So now I know for sure the problem is not related to a botched move or anything specifically regarding the ovztransfer.sh script. The fact that I cannot reliably snapshot/checkpoint a cPanel container under OVZ7 pretty much puts me at a stand still in terms of using OVZ7 in a production environment. Here are some relevant details: Hostnode: Virtuozzo Linux release 7.2 / Linux 3.10.0-327.36.1.vz7.18.7 VE: CentOS Linux release 7.2.1511 (Core) - Running a brand new install of the latest version of cPanel with about ~600 active users recently migrated to it using cPanel transfer tool / ~250GB of data. # prlctl snapshot 1035 Creating the snapshot... PRL_ERR_VZCTL_OPERATION_FAILED (Details: Failed to checkpoint the Container All dump files and logs were saved to /vz/private/1035/dump/{ce2b2c58-00ac-4e2f-b4da-e0a0dc594ff4}.fail Failed tp dump the Container, status pipe unexpectedly closed Failed to dump Container Failed to resume Container Failed to create snapshot ) Failed to create the snapshot: Unknown What I think is the relevant info from the dump.log file (04.143824) Error (criu/sk-inet.c:158): In-flight connection (l) for 924d83 (04.143831) Error (criu/sk-inet.c:160): In-flight connections can be ignored with the --skip-in-flight option. (04.143868) Error (criu/cr-dump.c:1322): Dump files (pid: 256864) failed with -1 (04.168423) Error (criu/cr-dump.c:1634): Dumping FAILED. I've also attached the full dump.log file as well.
Re: OpenVZ7 can't snapshot/suspend a cPanel VE
Are you sure this is related to cPanel? Can you chkpoint a non-cPanel container on OVZ7? Have you filed a bug report? I can tell you there was a bug in a recent OpenVZ Legacy kernel update that broke restore after reboot but they got that fixed after it was reported. Chances are it is just a bug that needs to be fixed once they know it is there.
No, not 100% sure it's related to cPanel. I do have another cPanel VM on the same hostnode that I can snapshot. Where is the recommended place to submit a bug report?
Submit bug reports to https://bugs.openvz.org They have been fixing OpenVZ Legacy kernel bugs fairly quickly after reports come in so good luck with yours.
Hi, thank you for reporting this here and in the jira: https://bugs.openvz.org/browse/OVZ-6824. Let's investigate and track the status of this issue in that bug. Hope the issue is simple and can be fixed soon.