Uninstall of MC/SG

[Jasti Kalyan Babu]

I have a MC/SG cluster with a single package.
There is only one shared LUN in the package and hence it forms the cluster lock PV.

I need to remove the package and the cluster and make the data on the disk available as an unshared VG to one system.

I anticipate the following steps.
- cmhaltpkg -v -P packagename
- cmdeleteconf -v -P packagename
- vgchange -a e VGNAME (node1)
- vgchange -c n VGNAME (node1)
- vgchange -a n VGNAME (node1)
- vgexport VGNAME (node2)
- cmhaltcl
- cmdeleteconf -v -C clustername

- vgchange -a y VGNAME (node1)
- mount ..... (node1)

I would appreciate it if there is something wrong with the above methodology.

Thanks in advance.
Jasti

[John Poff]

Hello,

Looks pretty good to me, just a couple of things I can think of:

1. Set the /etc/rc.config.d/cmcluster file so that the environment variable AUTOSTART_CMCLD is set to zero, so that your machine won't try to start/stop MC/SG at boot/shutdown.

2. On node1 be sure to put the entries in /etc/fstab for your filesystems so that they will get mounted at boot.

JP

[Stefan Farrelly]

Your commands look good but it may be even easier.

cmhaltcl
swremove
vgchange -a y
mount -a

I think thats all you should need, and to modify /etc/rc.config.d/netconf to unconfigure the extra lan cards (heartbeat plus maybe a standby lan).

[A. Clay Stephenson]

Your steps will work but you also need to to edit /etc/rc.config.d/cmcluster on each node and set AUTOSTART_CMCLD=0 so that the cluster does not attempt to form on reboot.

Clay

[linuxfan · Accepted solution]

Hi,

You can actually skip the vgchanges between cmdeleteconf packaganame and cmhaltcl and do a vgchange -c n and vgchange -a y after deleting the package and the cluster. Also i believe you can delete both the package and cluster in one go,

So this is another option,
cmhaltpkg -v pkgname
cmhaltcl -v
(Check to make sure cluster daemons are halted on both nodes)
cmdeleteconf -v -c clustername -p pkgname

On node2
vgexport vgshared

On node1
vgchange -c n /dev/vgshared
vgchange -a y /dev/vgshared

I don't remember if cmdeleteconf actually deletes the /etc/cmcluster directory, so you may want to clean that up as well (save some space in / directory ;)

Edit /etc/rc.config.d/cmcluster and modify the AUTO_START_CMCLD to 0.

Edit /etc/lvmrc to enable activating the /dev/vgshared on reboots, otherwise when node1 is rebooted, /dev/vgshared won't be activated.

Edit and Modify the /etc/fstab to mount the filesystems in /dev/vgshared.

-HTH
Ramesh

[Santosh Nair_1]

Minor point I'm sure, but make sure to update the /etc/fstab with the SG LVs and their corresponding mount points.

Also, you don't need to active the VG in exclusive mode first before doing a vgchange -c n, i.e. you could just

cmhaltcl -f, take down all the packages and the cluster
vgchange -c n VGNAME
vgchange -a y VGNAME
swremove
edit /etc/rc.config.d/netconf take out the heartbeat lan.
edit /etc/fstab add the SG LVs.
edit /etc/lvrc, change AUTO_VG_ACTIVATE to 1 and comment out everything but the return 0 in custom_vg_activation.

-Santosh

-Santosh

[linuxfan]

Hi,

One more thing, if you had updated the NIS/DNS or the /etc/hosts, you might want to remove the entries for the relocatable packages IPs /Heartbeat IPs.

Also check the /etc/rc.config.d/netconf file to remove any unnecessary IPs that are configured to be activated on reboots.

One more note of warning, when you stop using MC/SG, the shared disk is still seen on the other machine, and if you are working in a group, someone might mistake it for a free disk (on node2) and (even if you use SAM, SAM does not complain if this disk is seen and configured on another shared node) create a new filesystem, so you might want to disconnect the disk at the earliest from node2.

-Ramesh

[Thierry Poels_1]

hi,

don't forget to set AUTO_VG_ACTIVATE=1 in /etc/lvmrc (this was only mentionned by Santosh!).
(I did :(( but once bitten, twice shy ;))

good luck,
Thierry.


edit /etc/lvrc, change AUTO_VG_ACTIVATE to 1