NFS
m (HAGGER??????????????????????????????????????????? moved to NFS over redirect) |
(docs on DRBD setup) |
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== pmtpa == | == pmtpa == | ||
| − | /home, | + | === /home === |
| + | |||
| + | ==== The server ==== | ||
| + | |||
| + | A [http://www.drbd.org DRBD] cluster of [[nfs1]] and [[nfs2]] serve NFS /home. (At most) one of the two is primary at any point in time, and can read and write from the block device <tt>/dev/drbd1</tt>. The (other) secondary host can not write ''nor read'' from the block device... so /home cannot be mounted from it while the host is secondary. | ||
| + | |||
| + | DRBD has excellent [http://www.drbd.org/docs/about/ documentation], and repeating that here would be pointless. The most common administrative tasks are described [http://www.drbd.org/docs/working/ here]. | ||
| + | |||
| + | <tt>/etc/drbd.conf</tt> (must always be equal on both hosts): | ||
| + | <pre> | ||
| + | # drbd.conf for replication between nfs1 and nfs2 | ||
| + | # Written on 2009/11/23 by Mark Bergsma <mark@wikimedia.org> | ||
| + | |||
| + | global { | ||
| + | usage-count no; | ||
| + | } | ||
| + | |||
| + | common { | ||
| + | protocol C; | ||
| + | } | ||
| + | |||
| + | resource nfshome { | ||
| + | syncer { | ||
| + | rate 110M; | ||
| + | } | ||
| + | |||
| + | on nfs1 { | ||
| + | device /dev/drbd1; | ||
| + | disk /dev/mapper/mirror-nfshome; | ||
| + | address 10.3.0.1:7789; | ||
| + | meta-disk internal; | ||
| + | } | ||
| + | |||
| + | on nfs2 { | ||
| + | device /dev/drbd1; | ||
| + | disk /dev/mapper/mirror-nfshome; | ||
| + | address 10.3.0.2:7789; | ||
| + | meta-disk internal; | ||
| + | } | ||
| + | } | ||
| + | </pre> | ||
| + | |||
| + | The migration of NFS home off db20 onto nfs1/nfs2 was described extensively in the [[Db20 to NFS1-2 migration plan]]. | ||
| + | |||
| + | If the primary host goes down, the secondary can be promoted to primary. Use the following steps: | ||
| + | |||
| + | '''On the (failing?) primary (if accessible):''' | ||
| + | |||
| + | * Stop nfs-kernel-server | ||
| + | * Umount /home (so <tt>/dev/drbd1</tt> is unused) | ||
| + | * drbdadm secondary nfshome | ||
| + | |||
| + | '''On the secondary, to become the new primary host:''' | ||
| + | |||
| + | * drbdadm primary nfshome | ||
| + | * Mount /home (uncomment in <tt>/etc/fstab</tt>) | ||
| + | * Start nfs-kernel-server | ||
| + | |||
| + | * Then, migrate the service ip <tt>10.0.5.8</tt> to the appropriate host. | ||
| + | |||
| + | ==== Clients ==== | ||
| + | |||
| + | <tt>/etc/fstab</tt> entry: | ||
| + | |||
10.0.5.8:/home /home nfs bg,soft,udp,rsize=8192,wsize=8192,timeo=14,intr,nfsvers=3 0 0 | 10.0.5.8:/home /home nfs bg,soft,udp,rsize=8192,wsize=8192,timeo=14,intr,nfsvers=3 0 0 | ||
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[[Category:Current]] | [[Category:Current]] | ||
| + | [[Category:NFS]] | ||
Revision as of 20:26, 23 November 2009
Contents |
pmtpa
/home
The server
A DRBD cluster of nfs1 and nfs2 serve NFS /home. (At most) one of the two is primary at any point in time, and can read and write from the block device /dev/drbd1. The (other) secondary host can not write nor read from the block device... so /home cannot be mounted from it while the host is secondary.
DRBD has excellent documentation, and repeating that here would be pointless. The most common administrative tasks are described here.
/etc/drbd.conf (must always be equal on both hosts):
# drbd.conf for replication between nfs1 and nfs2
# Written on 2009/11/23 by Mark Bergsma <mark@wikimedia.org>
global {
usage-count no;
}
common {
protocol C;
}
resource nfshome {
syncer {
rate 110M;
}
on nfs1 {
device /dev/drbd1;
disk /dev/mapper/mirror-nfshome;
address 10.3.0.1:7789;
meta-disk internal;
}
on nfs2 {
device /dev/drbd1;
disk /dev/mapper/mirror-nfshome;
address 10.3.0.2:7789;
meta-disk internal;
}
}
The migration of NFS home off db20 onto nfs1/nfs2 was described extensively in the Db20 to NFS1-2 migration plan.
If the primary host goes down, the secondary can be promoted to primary. Use the following steps:
On the (failing?) primary (if accessible):
- Stop nfs-kernel-server
- Umount /home (so /dev/drbd1 is unused)
- drbdadm secondary nfshome
On the secondary, to become the new primary host:
- drbdadm primary nfshome
- Mount /home (uncomment in /etc/fstab)
- Start nfs-kernel-server
- Then, migrate the service ip 10.0.5.8 to the appropriate host.
Clients
/etc/fstab entry:
10.0.5.8:/home /home nfs bg,soft,udp,rsize=8192,wsize=8192,timeo=14,intr,nfsvers=3 0 0
Upload mounts:
amane:/export/upload /mnt/upload3 nfs bg,soft,udp,rsize=8192,wsize=8192,timeo=14,intr,nfsvers=3 0 0 storage1.wikimedia.org:/export/upload /mnt/upload4 nfs bg,soft,tcp,rsize=8192,wsize=8192,timeo=14 0 0
texvc output:
amane:/export/math /mnt/math nfs bg,soft,udp,rsize=8192,wsize=8192,timeo=14,intr,nfsvers=3 0 0
yaseo
No NFS anymore.
knams
Probably none. None on the squids anyway.
