6.4 Testing
3.0: Initialization LDAP Database
5.0: Heartbeat HA Configuration
Table of Contents
We have a 2 node cluster replicating data, its time to test a failover.
Step1
Start the heartbeat service on both nodes.
Step2
On node1 we can see the status of DRBD.
[root@node1 ~]# service drbd status drbd driver loaded OK; device status: version: 0.7.23 (api:79/proto:74) 0: cs:Connected st:Primary/Secondary ld:Consistent ns:1536 nr:0 dw:1372 dr:801 al:4 bm:6 lo:0 pe:0 ua:0 ap:0 [root@node1 ~]#
On node2 we can see the status of DRBD.
[root@node2 ~]# service drbd status drbd driver loaded OK; device status: version: 0.7.23 (api:79/proto:74) SVN Revision: 2686 build by root@node2, 2007-01-23 20:26:03 0: cs:Connected st:Secondary/Primary ld:Consistent ns:0 nr:1484 dw:1484 dr:0 al:0 bm:6 lo:0 pe:0 ua:0 ap:0
[root@node2 ~]#
That all looks good; we can see the devices are consistent and ready for use.
Step3
Now let’s check the mount point we created in the heartbeat haresources file.
We can see heartbeat has successfully mounted “/dev/drbd0 to the /data directory” of course your device will not have any data on it yet.
[root@node1 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/VolGroup00-LogVol00 35G 14G 20G 41% / /dev/hdc1 99M 21M 74M 22% /boot /dev/shm 506M 0 506M 0% /dev/shm /dev/drbd0 74G 37G 33G 53% /data [root@node1 ~]#
Step4
Login to node1 and execute the following command; once heartbeat is stopped it should only take a few seconds to migrate the services to node2.
[root@node1 ~]# service heartbeat stop Stopping High-Availability services: [ OK ]
[root@node1 ~]# service drbd status drbd driver loaded OK; device status: version: 0.7.23 (api:79/proto:74) SVN Revision: 2686 build by root@node1, 2007-01-23 20:26:13 0: cs:Connected st:Secondary/Primary ld:Consistent ns:5616 nr:85492 dw:90944 dr:2162 al:9 bm:260 lo:0 pe:0 ua:0 ap:0
We can see drbd change state to secondary on node1.
Step5
Now let’s check that status of DRBD on node2; we can see it has changed state and become the primary.
[root@node2 ~]# service drbd status drbd driver loaded OK; device status: version: 0.7.23 (api:79/proto:74) SVN Revision: 2686 build by root@node2, 2007-01-23 20:26:03 0: cs:Connected st:Primary/Secondary ld:Consistent ns:4 nr:518132 dw:518136 dr:17 al:0 bm:220 lo:0 pe:0 ua:0 ap:0 1: cs:Connected st:Primary/Secondary ld:Consistent ns:28 nr:520252 dw:520280 dr:85 al:0 bm:199 lo:0 pe:0 ua:0 ap:0
Check that node2 has mounted the device.
[root@node2 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/VolGroup00-LogVol00 35G 12G 22G 35% / /dev/hdc1 99M 17M 78M 18% /boot /dev/shm 506M 0 506M 0% /dev/shm /dev/hdh1 111G 97G 7.6G 93% /storage /dev/drbd0 74G 37G 33G 53% /data [root@node2 ~]#
Step5
Finally start the heartbeat service on node1 and be sure that all processes migrate back.