Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Wed, 27 Feb 2008, Lars Ellenberg wrote: > On Wed, Feb 27, 2008 at 01:07:04PM -0500, Nate Seif wrote: >> >> >> On Wed, 27 Feb 2008, Lars Ellenberg wrote: >> >>> On Tue, Feb 26, 2008 at 04:14:36PM -0500, Nate Seif wrote: >>>> Hello all: >>>> I intermittently experience the errors below while running DRBD and would >>>> like to correct whatever condition is causing DRBD to randomly lose pages. >>>> My hard disks and partitions are identical and have never given me >>>> problems previously. I don't see any other disk I/O errors in my logs. And >>>> it appears that occassionally (not always) these errors are preceded by a >>>> resync of the two disks. >>>> >>>> Why would DRBD "attempt to access beyond end of device"? >>>> >>>> I am running DRBD 8.06 on Gentoo Linux as I could not get my latest >>>> Gentoo kernel to load the DRBD module where version > 8.06. Metadata is >>>> "internal" and I'm running Protocol C. I'd be happy to post my drbd.conf >>>> page if necessary. >>>> >>>> >>>> Feb 26 08:21:46 <hostname> attempt to access beyond end of device >>>> Feb 26 08:21:46 <hostname> drbd0: rw=1, want=211992584, limit=211986944 >>>> Feb 26 08:21:46 <hostname> Buffer I/O error on device drbd0, logical block >>>> 26499072 >>>> Feb 26 08:21:46 <hostname> lost page write due to I/O error on drbd0 >>>> Feb 26 08:21:46 <hostname> attempt to access beyond end of device >>>> Feb 26 08:21:46 <hostname> drbd0: rw=1, want=211992592, limit=211986944 >>>> Feb 26 08:21:46 <hostname> Buffer I/O error on device drbd0, logical block >>>> 26499073 >>>> Feb 26 08:21:46 <hostname> lost page write due to I/O error on drbd0 >>>> >>>> >>>> Any ideas, tips, help, etc. is much appreciated. Thank you - >>> >>> let me guess: >>> you did mkfs /dev/sda1, not mkfs /dev/drbd0? >>> well, you screwed up. >> >> I did NOT mkfs on /dev/hda4. (I have DRBD running on a pair of IDE/PATA >> disks and no SATA drives in either system.) >> >> I partitioned my disks with fdisk. I have identical drives with >> identically sized partitions. I compiled the DRBD module, started DRBD, >> mounted /dev/drbd0 (not /dev/hda4), and formatted drbd0 with an ext3 >> file system on the primary only after I got DRBD up and running months >> ago. > > please do > > tune2fs -l /dev/mapper/vg00--bk1-root | > grep -e ^Block.count: -e ^Block.size: > > you get two numbers. > multiply those, you get the size (in bytes) > your ext3 thinks it is occupying. > which is the size of the partition you run the mkfs on, at the time of > the mkfs run, unless you used special options. > > now, do > grep -e hda4 -e drbd0 /proc/partitions > > you again get two numbers, this time unit is kilo byte. > that is the size of the partitions as the kernel sees them now. > according to the logs above (the limit= is unit sectors), > drbd0 will be 105993472 kB. > I dare say hda4 will be somewhat larger, my best guess, given the > information I have, is that hda4 will be 105996740 kB. > and that this also matches what the tune2fs reports. > >> My logs did not start recording these errors until several weeks ago. > > which probably only means that the file system slowly filled up, > and now starts actually _using_ those areas which are no longer there, > because they are now occupied by the drbd meta data. I have used very little (only 7%) of the space on /dev/drbd0. <hostname> ~ # df -h Filesystem Size Used Avail Use% Mounted on /dev/hda3 12G 6.2G 4.6G 58% / udev 10M 176K 9.9M 2% /dev shm 997M 0 997M 0% /dev/shm /dev/drbd0 100G 5.8G 89G 7% /rs2 <hostname> ~ # df Filesystem 1K-blocks Used Available Use% Mounted on /dev/hda3 11812248 6443008 4769204 58% / udev 10240 176 10064 2% /dev shm 1020808 0 1020808 0% /dev/shm /dev/drbd0 104332960 6037048 92996076 7% /rs2 Does DRBD shrink the file system on /dev/drbd0 periodically to accomodate its meta data? If so, is the kernel made aware of this? I seem to remember reading somewhere, though, that internal metadata was a fixed 128 MB at the end of the device. In my case, internal metadata should occupy 128 MB at end of /dev/hda4 and /dev/drbd0 should be correspondingly 128 MB smaller than /dev/hda4, correct? Thank you for your time, Lars - Nate > > -- > : Lars Ellenberg http://www.linbit.com : > : DRBD/HA support and consulting sales at linbit.com : > : LINBIT Information Technologies GmbH Tel +43-1-8178292-0 : > : Vivenotgasse 48, A-1120 Vienna/Europe Fax +43-1-8178292-82 : > __ > please use the "List-Reply" function of your email client. > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user >