vizz.info

Yet another VM blog http://www.vmprofessional.com/

Make sure you quiesce any services such as Oracle 10g DB in your VMware VMs before you snap them:

• Install VMware Tools in your VM
• Create /usr/sbin/pre-freeze-script
• Create /usr/sbin/post-thaw-script

Use vcbMounter to snapshot your live VMware VM which will call /usr/sbin/pre-freeze-script just BEFORE creating the snap and /usr/sbin/post-thaw-script approx 1 second AFTER the delta/diff/redo file has been created BUT before the original VMDK has been been exported via vmkfstools.

# cat /usr/sbin/pre-freeze-script

#!/bin/sh

#####################################

# DO NOT modify this file directly as it will be overwritten the next
# time the VMware Tools are installed.
#####################################

echo frez$(date) >> /var/log/snap

# cat /usr/sbin/post-thaw-script

#!/bin/sh

#####################################

# DO NOT modify this file directly as it will be overwritten the next
# time the VMware Tools are installed.
#####################################

echo thaw$(date) >> /var/log/snap

# tail /var/log/snap
frezWed Nov 28 11:26:20 GMT 2007
thawWed Nov 28 11:26:21 GMT 2007

To get the most out of your VMs and backup and restore them in the most reliable way you must install VMware tools in your guests.

As well as providing better mouse & video drivers it provides an API to the host providing IP, clock information and installs VM startup, VM shutdown, VM freeze & VM thaw scripts /usr/sbin/pre-freeze-script and /usr/bin/post-thaw-script.

http://www.vmware.com/pdf/vi3_vm_backup.pdf

Setup NFS

Setup SSH RSA login

Setup mailx

Setup host,username,password in /etc/vmware/backuptools.conf

Create vcbBack, vcbRest and vcbCron

Create cronjob

Sit back and relax

backup-vms-between-two-vmware-esx-servers-using-just-nfs-ssh-and-vcb-utilities

After backing up a VMWESX VM with vcbMounter you can use vcbRestore to perform a quick restore on another ESX server

Edit the catalog file

• change SOURCE hostname to DEST hostname
• check the same “resource pool” exists on DEST host (if not change it so it does)

for example

• host=myserver.mydomain

• resourcepool= “/ha-folder-root/ha-datacenter/host/myserver.mydomain/Resources”

Here’s a CentOS 4 VM with 4 snapshots, in each snapshot I added a 40M file and in two of the snapshots i snapped the memeory as well.

Note a memory snapshot file is ALWAYS created if it doesn’t contain anything !

The .VMSD contains a snapshot definition !

-rw——-    1 root     root         8.0G Nov 26 17:26 cent4-flat.vmdk
-rw——-    1 root     root          334 Nov 21 12:39 cent4.vmdk

-rw——-    1 root     root         1.4K Nov 26 17:31 cent4.vmsd

-rw——-    1 root     root          48M Nov 26 17:28 cent4-000001-delta.vmdk
-rw——-    1 root     root          219 Nov 26 17:27 cent4-000001.vmdk
-rw——-    1 root     root          18K Nov 26 17:27 cent4-Snapshot1.vmsn

-rw——-    1 root     root          48M Nov 26 17:29 cent4-000002-delta.vmdk
-rw——-    1 root     root          226 Nov 26 17:28 cent4-000002.vmdk
-rw——-    1 root     root         257M Nov 26 17:28 cent4-Snapshot2.vmsn

-rw——-    1 root     root          48M Nov 26 17:31 cent4-000003-delta.vmdk
-rw——-    1 root     root          226 Nov 26 17:29 cent4-000003.vmdk
-rw——-    1 root     root         257M Nov 26 17:29 cent4-Snapshot3.vmsn

-rw——-    1 root     root          16M Nov 26 17:31 cent4-000004-delta.vmdk
-rw——-    1 root     root          226 Nov 26 17:31 cent4-000004.vmdk
-rw——-    1 root     root          18K Nov 26 17:31 cent4-Snapshot4.vmsn

Basically during the VMware ESX two phase live backup process

ESX 2 uses .redo and .redo.redo “redo files” while

ESX 3 uses -0001-delta.vmdk and -0002-delta.vmdk “snapshots”
In VMWESX 2 .redo and .redo.redo are used for live backups

Running

var.vmdk

Backup started

var.redo

var.vmdk

Backup completed (applying redo)

var.redo.redo

var.redo

var.vmdk

In VMWESX 3 snapshots -000001-delta.vmdk and -000002-delta.vmdk are used

Running VM

var-flat.vmdk

var.vmbk

Backup started

var-000001-delta.vmdk

var-000001.vmdk

Backup completed (applying, commiting, delete all, removing snapshots)

var-000002-delta.vmdk

var-000002.vmdk

var-000001-delta.vmdk

var-000001.vmdk

var-flat.vmdk

var.vmdk

VMW ESX 3i is “functionally equivalent but the servers “local” service console has been removed. VMW ESX 3i uses only 32M so it can even be embedded in the hosts firmware.Since you can no longer login locally you must administer it remotely by using VMWVC, VMWVIC, remote command line or an agent that uses VIMAPI or CIM.

For example

• esxcfg-* is replaced by vicfg-*
• esxtop is replaced by resxtop

mountvm.exe

http://www.petri.co.il/vmware-consolidated-backup-utilities.htm

http://www.howtoforge.com/centos_5.0_xen