From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Justin Stephenson" Subject: Re[2]: RAID 6 crashes system when being accessed Date: Sat, 05 Jul 2014 01:08:20 +0000 Message-ID: References: <53B701B9.7060702@hardwarefreak.com> Reply-To: "Justin Stephenson" Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset=utf-8 Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <53B701B9.7060702@hardwarefreak.com> Sender: linux-raid-owner@vger.kernel.org To: stan@hardwarefreak.com, linux-raid@vger.kernel.org List-Id: linux-raid.ids Hi, Thanks for your reply. I should clarify that the crashes continue to be an issue in the absence of any power outage so this issue is now independent of power. I mentioned the UPS only with the thought that my problems may have been caused by a sudden power-down. Please let me know if there are any logs or status print outs I could pull to help troubleshoot this. Thanks Again, - J ------ Original Message ------ From: "Stan Hoeppner" To: "Justin Stephenson" ; linux-raid@vger.kernel.org Sent: 04/07/2014 3:34:17 PM Subject: Re: RAID 6 crashes system when being accessed >On 7/4/2014 9:11 AM, Justin Stephenson wrote: >> Hello, >> >> I am experiencing some issues with my md raid. It is crashing my >>system >> when accessed with any "verve". The reboot initiates a resync of the >> raid. I have gone through the crash/reboot/resynced a number of times >> now and the crash happens within minutes of mounting the raid. >> >> Here are some details: >> >> - It is a raid 6 with 7 3TB devices. >> - Formatted as EXT4 >> - mdadm v3.2.6 - 25th October 2012 >> - centos 6.5 kernel 2.6.32-431.3.1.el6.x86_64 >> - It has been running flawlessly for the previous 6 months. >> - I have a cron script running that resyncs monthly. >> - When the raid is unmounted, the system runs fine. (I have an >> additional "dumb" hardware raid 1 for dailies attached to an ESATA >>port. >> This runs perfectly). >> - I am in the process of re-syncing the raid 6 again right now. >> - I have run an fsck on the raid volume after it was fully synced and >> everything came up clean. >> >> - there have been lots of power outages the last while with the hot >> summer in Toronto. My UPS shuts the system down for me, though I >>think I >> can correlate the issues with the power outages. > >This sounds like the UPS is cutting power to the system before the >shutdown sequence completes, before the array is stopped. This assumes >you are already using apcupsd or similar. If you are check the >configuration to make sure the system has plenty of time to shutdown >after the UPS sends notification to the system. If you are not, then >this will always happen as the UPS is simply cutting power when the >battery gets low. > >Note that if the UPS is undersized for this system and only yields a >few >minutes of on-battery time, it may simply not have enough juice to keep >the machine up throughout the shutdown process. > >In summary, either your shutdown software isn't configured properly, >you >are not using it, or the UPS is too small. This isn't an md problem. > > >Cheers, > >Stan