Re: Re[2]: [zfs-discuss] Re: Difference between ZFS and UFS with one LUN froma SAN
Hi Robert, MPxIO had correctly moved the paths. More than one path to controller A was OK, and one patch to controller A for each LUN was active when controller B was rebooted. I have a hunch that the array was at fault, because it also rebooted a Windows server with LUNs only on Controller A. In the case of the Windows server Engenios RDAC was handling multipathing. Overall, not a big deal, I just wouldn't trust the array to do a hitless commanded controller failover or firmware upgrade. -J On 12/22/06, Robert Milkowski <[EMAIL PROTECTED]> wrote: Hello Jason, Friday, December 22, 2006, 5:55:38 PM, you wrote: JJWW> Just for what its worth, when we rebooted a controller in our array JJWW> (we pre-moved all the LUNs to the other controller), despite using JJWW> MPXIO ZFS kernel panicked. Verified that all the LUNs were on the JJWW> correct controller when this occurred. Its not clear why ZFS thought JJWW> it lost a LUN but it did. We have done cable pulling using ZFS/MPXIO JJWW> before and that works very well. It may well be array-related in our JJWW> case, but I hate anyone to have a false sense of security. Did you first check (with format for example) if LUNs were really accessible? If MPxIO worked ok and at least one path is ok then ZFS won't panic. -- Best regards, Robertmailto:[EMAIL PROTECTED] http://milek.blogspot.com ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
RE: Re[2]: [zfs-discuss] Re: Difference between ZFS and UFS with one LUN froma SAN
More specifically, if you have the controllers in your array setup in an active/passive setup, and they have a failover timeout of 30 seconds, and the hba's have a failover timeout of 20 seconds, when it goes to failover and cannot write to the disks... I'm sure *bad things* will happen. Again, I haven't tested this scenario, but I can only imagine it's not something that can be/should be/is recovered from gracefully. --Tim -Original Message- From: Robert Milkowski [mailto:[EMAIL PROTECTED] Sent: Friday, December 22, 2006 3:18 PM To: Jason J. W. Williams Cc: Tim Cook; zfs-discuss@opensolaris.org; Shawn Joy Subject: Re[2]: [zfs-discuss] Re: Difference between ZFS and UFS with one LUN froma SAN Hello Jason, Friday, December 22, 2006, 5:55:38 PM, you wrote: JJWW> Just for what its worth, when we rebooted a controller in our array JJWW> (we pre-moved all the LUNs to the other controller), despite using JJWW> MPXIO ZFS kernel panicked. Verified that all the LUNs were on the JJWW> correct controller when this occurred. Its not clear why ZFS thought JJWW> it lost a LUN but it did. We have done cable pulling using ZFS/MPXIO JJWW> before and that works very well. It may well be array-related in our JJWW> case, but I hate anyone to have a false sense of security. Did you first check (with format for example) if LUNs were really accessible? If MPxIO worked ok and at least one path is ok then ZFS won't panic. -- Best regards, Robertmailto:[EMAIL PROTECTED] http://milek.blogspot.com ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re[2]: [zfs-discuss] Re: Difference between ZFS and UFS with one LUN froma SAN
Hello Jason, Friday, December 22, 2006, 5:55:38 PM, you wrote: JJWW> Just for what its worth, when we rebooted a controller in our array JJWW> (we pre-moved all the LUNs to the other controller), despite using JJWW> MPXIO ZFS kernel panicked. Verified that all the LUNs were on the JJWW> correct controller when this occurred. Its not clear why ZFS thought JJWW> it lost a LUN but it did. We have done cable pulling using ZFS/MPXIO JJWW> before and that works very well. It may well be array-related in our JJWW> case, but I hate anyone to have a false sense of security. Did you first check (with format for example) if LUNs were really accessible? If MPxIO worked ok and at least one path is ok then ZFS won't panic. -- Best regards, Robertmailto:[EMAIL PROTECTED] http://milek.blogspot.com ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
