xen.independent_wallclock=1 Hi Folks,
Well, last night, I transitioned my production system from physical
(running directly on Debian Lenny on bare metal) to running inside a VM
on Xen. And it went incredibly smoothly.
First off - thanks to those of you who sent advice. You saved me a lot
of headaches.
Second, here's a summary of what I did - in case it might be useful to
others:
1. Set up my target machine:
- starting condition: Dom0 = Debian Lenny,
xen-linux-system-2.6.26-2-xen-686, plus a few tweaks
- create three logical volumes: root, swap, backup ("backup" is another
volume I use for backups and things)
- set these up as DRBD devices (not really relevant to this discussion)
- make filesystems on root and backup
- mkswap on swap
2. Bring down production server, reboot with a rescue CD (SysRescueCD)
- assign an unused IP
- set up to allow root login via ssh
3. Transfer Data
- mount the original root and backup volumes
- move data (took a LONG time) - thanks to whomever sent this recipe! -
typed these on the target (new) machine
rsync -avzH --numeric-ids -e ssh root@<IP>:/mnt/mydir/backup/* /mnt/backup
rsync -avzH --numeric-ids -e ssh root@<IP>:/mnt/mydir/root/* /mnt/root
4. Set up <server>.cfg file:
# notes: this is based on an earlier file generated by xen-tools
kernel = '/boot/vmlinuz-2.6.26-2-xen-686'
ramdisk = '/boot/initrd.img-2.6.26-2-xen-686'
memory = '1024'
disk = [
'drbd:root,xvda1,w',
'drbd:swap,xvda2,w',
'drbd:backup,xvda3,w'
]
root = '/dev/xvda1 ro'
vif = [ 'ip=xx.xx.xx.xx,mac=00:16:3E:BE:68:F5' ]
#where xx.xx.xx.xx = primary address of the original system
name = 'server1'
on_poweroff = 'destroy'
on_reboot = 'restart'
on_crash = 'restart'
#this is to fix a bug in clock sync, per advice at
#http://wiki.debian.org/Xen#A.27clocksource.2BAC8-0.3ATimewentbackwards.27
extra="clocksource=jiffies"
4. while still mounted, edit /mnt/root/etc/fstab to read:
proc /proc proc defaults 0 0
/dev/xvda1 / ext3 errors=remount-ro 0 1
/dev/xvda2 none swap sw 0 0
/dev/xvda3 /backup ext3 defaults 0 2
5. umount the two newly initialized volumes
6. start it up
xm create -c newserver1.cfg
and it ran - the first time!!!!
note: for some reason, the console stops responding after boot, but I
can log in via ssh, and all the processes run, mail flows, web sites are
up, etc. - the console reports messages on shutdown
7. log into the VM and clean a few things up
- turn off some services that are not relevant inside a VM (e.g, acpi,
hwclock)
- add " xen.independent_wallclock=1" to /etc/sysctl.conf; sysctl -p
#see above note re. time bug, note that NTP is running inside the VM
8. a few things I need to track down and fix
- getting this entry in the bootlog (doesn't seem to be effecting
anything, though)
Mon May 17 22:25:22 2010: modprobe: FATAL: Could not load
/lib/modules/2.6.26-2-xen-686/modules.dep: No such file or directory
- get the console to respond
Again, thanks to all who provided advice.
Miles Fidelman
--
In theory, there is no difference between theory and practice.
In<fnord> practice, there is. .... Yogi Berra
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|
Home