Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Hello Georges,
What is the output of the "/sbin/drbdsetup /dev/nb1 show" on each node ?
Best regards.
Francis
> Message: 7
> Date: Mon, 19 Jan 2004 15:42:06 -0500
> From: george young <gry at ll.mit.edu>
> To: drbd-user at lists.linbit.com
> Subject: Re: [DRBD-user] mirror config questions for manual failover
> Reply-To: gry at ll.mit.edu
> Organization: MIT Lincoln Laboratory
>
> Some clarifications:
> On Sun, 18 Jan 2004 22:18:51 -0500
> george young <gry at ll.mit.edu> threw this fish to the penguins:
>
>
>>> [drbd-0.6.10, Suse 8.2 x86 linux 2.4.20-4GB-SMP, 2 nodes, pvt 100Mb
>>> net]
>>> I have two nodes, pig-app and pig-db. Default config is that
>>> pig-app has
>>> the active copy of /home(36GB), pig-db has /db(1GB), each DRBD
>>> mirrored to
>>> the other. If and *only if* an administrator decides that one node is
>>> down, she runs a script on the remaining node to take over the other's
>>> file system (and switch ip's around so users get the new host). I'm
>>> having trouble getting the right drbd commands for this script. I also
>>> see very slowww syncing time... Both are are reiser file systems.
>>> There is a private 100Mbit ethernet between the two nodes.
>>
>>
>>
>
> The 100Mb private net seems healthy: tar-rsh-tar gets me 7.5MB/s.
> Without the tar and fs overhead I get 7.9MB/sec.
>
> With --sync-min=10M and fsckcmd=/bin/true and separate --sync-groups
> and removing the disconnect/net pair of commands, I get 1h44m sync
> for the 36G partition, i.e. 5.8MB/s. It would be nice to do 20%
> better, but clearly not a lot faster until I get gigabit ethernet.
>
>
>>> I use the HA-Linux "IPaddr" script, but heatbeat is *not* enabled.
>>>
>>> Here's my script for pig-app to grab the /db filesystem from pig-db:
>>> ------------------------------------------------------------
>>> if ping -c 1 pig-db; then
>>> rsh -n pig-db /usr/local/etc/ha.d/resource.d/datadisk drbd_db
>>> stop &
>>> sleep 30
>>> fi
>>
>>
>>
>
> I think I had put these in hoping to avoid a long sync delay.
> I'll take them out.
> #> /sbin/drbdsetup /dev/nb1 disconnect
> #> /sbin/drbdsetup /dev/nb1 net 10.0.0.115:7789 10.0.0.114:7789 C
>
>>> /usr/local/etc/ha.d/resource.d/datadisk drbd_db start
>>
>>
>>
>
> I *do* start other services in this script: samba, postgres,
> and the roving service IP addresses were omitted here for brevity.
>
>
>>> ------------------------------------------------------------
>>> I'm trying to assure that I don't get into a 2-hour long sync while
>>> users are screaming. After correcting the problem, I can revert
>>> off-hours, so that time is not critical.
>>> Does this script make sense? How could it be better?
>>>
>>> I am also frustrated that it takes 2 hours to sync 36G over a 100Mbit
>>> private net. That's a rate of about 5 Mbytes/sec. Disks on both hosts
>>> are fast hardware raids. Am I missing something?
>>>
>>> Below is my(common) drbd.conf:
>>> ------------------------------------------------------------
>>> resource drbd_home {
>>> protocol = C
>>> fsckcmd = fsck -p -y
>>
>>
>>
> I'll change this to /bin/true
>
>
>>> disk {
>>> disk-size = 36707364k
>>> }
>>> net {
>>> sync-min = 500k
>>
>>
>>
> I'll change this to sync-min=10M
>
>
>>> sync-max = 100M # maximal average syncer bandwidth
>>> tl-size = 5000 # transfer log size, ensures strict write
>>> ordering
>>> timeout = 60 # 0.1 seconds
>>> connect-int = 10 # seconds
>>> ping-int = 10 # seconds
>>
>>
>>
>
> I'll add sync-group=1
>
>>> }
>>> on pig-app {
>>> device = /dev/nb0
>>> disk = /dev/rd/c0d0p5
>>> address = 10.0.0.115
>>> port = 7788
>>> }
>>> on pig-db {
>>> device = /dev/nb0
>>> disk = /dev/rd/c0d2p1
>>> address = 10.0.0.114
>>> port = 7788
>>> }
>>> }
>>> resource drbd_db {
>>> protocol = C
>>> fsckcmd = fsck -p -y
>>> disk {
>>> disk-size = 1052184k
>>> }
>>> net {
>>> sync-min = 500k
>>> sync-max = 100M # maximal average syncer bandwidth
>>> tl-size = 5000 # transfer log size, ensures strict write
>>> ordering
>>> timeout = 60 # 0.1 seconds
>>> connect-int = 10 # seconds
>>> ping-int = 10 # seconds
>>
>>
>>
>
> I'll add sync-group=2
>
>>> }
>>> on pig-app {
>>> device = /dev/nb1
>>> disk = /dev/rd/c0d0p3
>>> address = 10.0.0.115
>>> port = 7789
>>> }
>>> on pig-db {
>>> device = /dev/nb1
>>> disk = /dev/rd/c0d0p1
>>> address = 10.0.0.114
>>> port = 7789
>>> }
>>> }
>>>
>>
>>
>
> -- "Are the gods not just?" "Oh no, child. What would become of us if
> they were?" (CSL)
>
>
>
>
Best regards.
Francis