What does that mean - consistency group every 30 seconds? What's TPC? Do you have consistency at any given time - that is are all your writes applied in order and no write that happened at time x failed to make it when one write at time x+1 did make it? Across all your control units and disk subsystems? If you do, then its like having the rug pulled out from under you (like a VM abend or something). You will have to go through fsck when you come back up and if you're running journaled file systems you will likely be OK. Of course, file level backups of unrecreatable stuff would still be desirable for things that failed to come out of this OK; realizing that their RPO would be different and adjustments made accordingly for that.
If you go all the way to single user mode, why not just go all the way down and be sure? Marcy "This message may contain confidential and/or privileged information. If you are not the addressee or authorized to receive this for the addressee, you must not use, copy, disclose, or take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation." -----Original Message----- From: Linux on 390 Port [mailto:[email protected]] On Behalf Of Melancon, Ruddy Sent: Friday, October 16, 2009 2:07 PM To: [email protected] Subject: [LINUX-390] TPC Replication and Linux We are currently doing Global Mirroring creating a "consistency group" every 30 seconds. What impact will this have during a recovery situation when we implement zVM and zLinux. The concern is in regard to Linux caching of output and the potential loss of disk metadata. Can we be assured that Linux will recover during a disaster situation. We do plan on doing a flashcopy of Linux volumes after placing the Linux images in single user mode. Ruddy A. Melancon IT Systems Specialist, Senior Alabama Department of Transportation 334-353-6323 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
