General Discussion

Restore the OS from the boot LUN snapshot




For the Converged infra, using the Flexpod solution, where the End server OS is running from the Boot LUN, i want to clarify if we capture the Snapshots over the Volume which contains the boot Lun, when OS is currenly Operating not is shut down state.


Will it be feasible in case of any issue with the OS, and if we restore the LUN as file from that volume for the OS, Or the Restore of the LUN (snapshot taken while OS was running) from snapshot does not work or not recommonded.


In such cases, if we need to use the snapshot as the backup of the boot lun, what should be the recommonded approch.



Thanks in adavnce..






You can take normal snapshot of the SAN BOOT drive but the copy will not be crash-consistent. all the modern OS and software likely to boot OK (Just like after hard shut down) but some might not.


In Windows you can take crash-consistent snapshot with SnapDrive for SAN BOOT LUNs


But for Linux i didnd't found such option. maybe you can just put your critical files on a mountpoint. so you can have an OS crash-consistent copy from the last time it was shut down and snapshot has taken. and more frequent crash-consistent snapshot for the important folders.


it's also important to remember that this snapshot are not app consistent, and you may need to first freeze the IO on the apps before taking this crash-consistent one.



Gidi Marcus (Linkedin) - Storage and Microsoft technologies consultant - Hydro IT LTD - UK