Failover Cluster keszitese - Ubuntu 8.04 heartbeat drbd ocfs2

OCFS2

http://oss.oracle.com/projects/ocfs2/ OCFS2 is a Cluster File System which allows simultaneous access from many nodes. We will set this on our drbd device to access it from both nodes simultaneously. While configuring OCFS2 we provide the information about nodes, which will access the file system later. Every Node that has a OCFS2 file system mounted, must regularly write into a meta-data of file system, letting the other nodes know that node is still alive.

Installation

sudo apt-get install ocfs2-tools ocfs2console

Configuration

Edit /etc/ocfs2/cluster.conf as follows

sudo vi /etc/ocfs2/cluster.conf

#/etc/ocfs2/cluster.conf
node:
ip_port = 7777
ip_address = 192.168.0.128
number = 0
name = node1
cluster = ocfs2
node:
ip_port = 7777
ip_address = 192.168.0.129
number = 1
name = node2
cluster = ocfs2
cluster:
node_count = 2
name = ocfs2

reconfigure ocfs2 with following command with their default values

dpkg-reconfigure ocfs2-tools

sudo /etc/init.d/o2cb restart
sudo /etc/init.d/ocfs2 restart

drbd8

Installation

http://en.wikipedia.org/wiki/Drbd

The advantage of drbd8 over drbd7 is: It allows the drbd resource to be “master” on both nodes and so can be mounted read-write. We will build drbd8 modules and load it in kernel. For that we need packages “build-essential” and “kernel-headers-xen”

sudo apt-get install drbd8-utils build-essential linux-headers-xen

sudo update-modules
sudo modprobe drbd

This builds the drbd module kernel/drivers/block/drbd.ko against the current running kernel. A default configuration file is installed as /etc/drbd.conf

Configuration

Edit the /etc/drbd.conf

sudo vi /etc/drbd.conf

#/etc/drbd.conf
global {
usage-count yes;
}
common {
syncer { rate 10M; }
}
resource r0 {
protocol C;
handlers {
pri-on-incon-degr "echo o > /proc/sysrq-trigger ; halt -f";
pri-lost-after-sb "echo o > /proc/sysrq-trigger ; halt -f";
local-io-error "echo o > /proc/sysrq-trigger ; halt -f";
outdate-peer "/usr/sbin/drbd-peer-outdater";
}
startup {
}
disk {
on-io-error detach;
}
net {
allow-two-primaries;
after-sb-0pri disconnect;
after-sb-1pri disconnect;
after-sb-2pri disconnect;
rr-conflict disconnect;
}
syncer {
rate 10M;
al-extents 257;
}
on node1 {
device /dev/drbd0;
disk /dev/sda3;
address 192.168.0.128:7788;
flexible-meta-disk internal;
}
on node2 {
device /dev/drbd0;
disk /dev/sda3;
address 192.168.0.129:7788;
meta-disk internal;
}
}

“ allow-two-primaries” option in net section of drbd.conf allows the resource to be mounted as “master” on both nodes. Copy the /etc/drbd.conf to node2 and restart drbd on both nodes with following command.

Itt mar elore fol kell tenni a hearbeatet, mert a drbd jogosultsagainak kell a hearbeat user.
You need install these packcages before start drbd.

sudo apt-get install heartbeat-2 heartbeat-2-gui

sudo /etc/init.d/drbd restart

!!!!!!
Ha nem tud letrehozni arra particora, mert mar erzekel rajta valami filerendszert akarmit, akkor o is azt ajanlja hogy irjuk tele nullakkal:

dd if=/dev/zero bs=1M count=1 of=/dev/sdb2; sync
dd if=/dev/zero bs=1M count=1 of=/dev/sda2; sync

drbdadm create-md r0
drbdadm -- -o primary r0
mkfs /dev/drbd0

!!!!!!!

If you check the status it looks like this

suddo /etc/init.d/drbd status
drbd driver loaded OK; device status:
version: 8.0.3 (api:86/proto:86)
SVN Revision: 2881 build by root@node1, 2008-01-20 12:48:36
0: cs:Connected st:Secondary/Secondary ds:UpToDate/UpToDate C r---
ns:143004 nr:0 dw:0 dr:143004 al:0 bm:43 lo:0 pe:0 ua:0 ap:0
resync: used:0/31 hits:8916 misses:22 starving:0 dirty:0 changed:22
act_log: used:0/257 hits:0 misses:0 starving:0 dirty:0 changed:0

change the resource to “master” with following command on both nodes

sudo drbdadm primary r0

and check the status again

sudo /etc/init.d/drbd status
drbd driver loaded OK; device status:
version: 8.0.3 (api:86/proto:86)
SVN Revision: 2881 build by root@node1, 2008-01-20 12:48:36
0: cs:Connected st:Primary/Primary ds:UpToDate/UpToDate C r---
ns:143004 nr:0 dw:0 dr:143004 al:0 bm:43 lo:0 pe:0 ua:0 ap:0
resync: used:0/31 hits:8916 misses:22 starving:0 dirty:0 changed:22
act_log: used:0/257 hits:0 misses:0 starving:0 dirty:0 changed:0

As you can see resource is “master” on both nodes Th drbd device is now accessible under /dev/drbd0

---

Nagyon orulunk meg minden, de nekem ugy szetesett az elso drbd-m mint a sicc, es nem is tudtam elsore visszacsinalni. syslogba is csak annyi volt hogy drbdadm split-brain....de ezzel nem tudtam megoldani.
mind2 gepen Standalone lett az allapot

drbdadm disconnect all #mind2 gepen
drbdadm pri-lost r0 #mind2 gepen

drbdadm connect r0

---

File system

We can now create a file system on /der/drbd0 by following command

sudo mkfs.ocfs2 /dev/drbd0

This can be mounted on both nodes simultaneously with

sudo mkdir /drbd0
sudo mount.ocfs2 /dev/drbd0 /drbd0

Now we have a common storage which will be synchronized with drbd on both nodes

Init script

We have to make sure that after reboot, the system will set drbd resources again to “master” and mount those on “/drbd0” before starting Heartbeat and Xen machines.

Edit /etc/init.d/mountdrbd.sh

sudo vi /etc/init.d/mountdrbd.sh

#/etc/init.d/mountdrbd.sh
drbdadm primary r0
mount.ocfs2 /dev/drbd0 /mnt

make it executable and add symbolic link to this under /etc/rc3.d/S99mountdrbd.sh

sudo chmode +x /etc/init.d/mountdrbd.sh
sudo ln -s /etc/init.d/mountdrbd.sh /etc/rc3.d/S99mountdrbd.sh

Actually this step can be integrated also in Heartbeat by adding appropriate resources to the configuration. But as time being we will do this with script.

Heartbeat2

http://www.linux-ha.org/Heartbeat

Installation

Now we can install and setup Heartbeat 2

Ezt kellett drbd elott:
You did it:
sudo apt-get install heartbeat-2 heartbeat-2-gui

Edit /etc/ha.d/ha.cf

sudo vi /etc/ha.d/ha.cf

#/etc/ha.d/ha.cf
crm on
bcast eth0
node node1 node2

and restart heartbeat2 with

sudo /etc/init.d/heartbeat restart

Es innet teljesen mas utat valasztottam mert a stonith nalam folyamatos rebootokat okozott es nem tudtam belole kimaszni.
Igy a CRM es configot lecsereltem sima haresource-ra.

De azzal az ocfs2-t nem kezelni igy nem a legjobb megoldast kaptam. Reboot utan ujra kell csinalni ocfs2-t.

Szoval ezek utan ezt a leirast alkalmaztam:

http://www.howtoforge.org/set-up-a-loadbalanced-ha-apache-cluster-ubunt…