People who are used to manage our network devices through ifconfig, we find some trouble when putting a virtual IP in pacemaker, because we can’t see it. If we type ip addr there it is, but not with ifconfig. To make it visible we just need to use iflabel=”label” option, and we will see the IP, and with “ip addr” we will now fast which is the server IP and which is the service IP in pacemaker:

#crm configure show
(...)
primitive IP_VIRTUAL ocf:heartbeat:IPaddr2
params ip="10.0.0.11" cidr_netmask="32" iflabel="IP_VIRTUAL"
op monitor interval="3s"
meta target-role="Started"
(...)


IMPORTANT: Device label accept only 10 characters. If we put more than 10, pacemaker won’t be able to start the virtual IP and will fail (this gave me some headaches :D). Make sure you put 10 characters at most.

Without iflabel it doesn’t appear in ifconfig and isn’t labeled in ip addr:

# ip addr
1: lo: mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:50:56:9e:3c:94 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.1/24 brd 10.0.0.255 scope global eth0
inet 10.0.0.11/32 brd 10.0.0.11 scope global eth0
inet 10.0.0.12/32 brd 10.04.0.12 scope global eth0
inet 10.0.0.13/32 brd 10.0.0.13 scope global eth0
inet 10.0.0.14/32 brd 10.0.0.14 scope global eth0
inet6 fe80::250:56ff:fe9e:3c94/64 scope link
valid_lft forever preferred_lft forever
# ifconfig
eth0 Link encap:Ethernet HWaddr 00:50:56:9E:3C:94
inet addr:10.0.0.1 Bcast:10.10.0.255 Mask:255.255.255.0
inet6 addr: fe80::250:56ff:fe9e:3c94/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1825681745 errors:0 dropped:0 overruns:0 frame:0
TX packets:2044189443 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:576307237739 (536.7 GiB) TX bytes:605505888813 (563.9 GiB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:924190306 errors:0 dropped:0 overruns:0 frame:0
TX packets:924190306 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:415970933288 (387.4 GiB) TX bytes:415970933288 (387.4 GiB)

However, if we use iflabel, there they are:

[[email protected] ~]# ip addr
1: lo: mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth1: mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:50:56:9e:3c:9c brd ff:ff:ff:ff:ff:ff
inet 10.0.0.1./24 brd 10.254.1.255 scope global eth1
inet 10.0.0.11/32 brd 10.0.0.11 scope global eth1:nginx-ncnp
inet 10.0.0.12/32 brd 10.0.0.12 scope global eth1:nginx-clnp
inet 10.0.0.13/32 brd 10.0.0.13 scope global eth1:hap-ncnp
inet 10.0.0.14/32 brd 10.254.1.14 scope global eth1:hap-clnp
inet6 fe80::250:56ff:fe9e:3c9c/64 scope link
valid_lft forever preferred_lft forever
[[email protected] ~]# ifconfig
eth1 Link encap:Ethernet HWaddr 00:50:56:9E:3C:9C
inet addr:10.0.0.1 Bcast:10.0.0.255 Mask:255.255.255.0
inet6 addr: fe80::250:56ff:fe9e:3c9c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:322545491 errors:0 dropped:0 overruns:0 frame:0
TX packets:333825895 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:92667389749 (86.3 GiB) TX bytes:93365772607 (86.9 GiB)

eth1:hap-clnp Link encap:Ethernet HWaddr 00:50:56:9E:3C:9C
inet addr:10.0.0.12 Bcast:10.254.1.52 Mask:255.255.255.255
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

eth1:hap-ncnp Link encap:Ethernet HWaddr 00:50:56:9E:3C:9C
inet addr:10.0.0.11 Bcast:10.254.1.51 Mask:255.255.255.255
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

eth1:nginx-clnp Link encap:Ethernet HWaddr 00:50:56:9E:3C:9C
inet addr:10.0.0.13 Bcast:10.254.1.32 Mask:255.255.255.255
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

eth1:nginx-ncnp Link encap:Ethernet HWaddr 00:50:56:9E:3C:9C
inet addr:10.0.0.14 Bcast:10.254.1.30 Mask:255.255.255.255
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:4073 errors:0 dropped:0 overruns:0 frame:0
TX packets:4073 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1136055 (1.0 MiB) TX bytes:1136055 (1.0 MiB)

Much better this way

More info here: http://linux.die.net/man/7/ocf_heartbeat_ipaddr2