So, the IPaddr2 script can just add an IP to an existing VLAN, but it doesn't call vconfig; it appears that one must have the VLAN already configured.

It can also add a label to the IP (which isn't useful).

So, to bring up a VLAN IP, at a bare minimum:

 [root@molly ~]# vconfig add eth0 300
 Added VLAN with VID == 300 to IF -:eth0:-
 [root@molly ~]# ip addr add 172.31.31.2/24 dev eth0.300
 [root@molly ~]# ip addr list dev eth0.300
 6: eth0.300@eth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop  
             link/ether 54:52:00:06:f7:66 brd ff:ff:ff:ff:ff:ff inet 
             172.31.31.2/32 scope global eth0.300
 [root@molly ~]# vconfig set_flag eth0.300 1
 Set flag on device -:eth0.300:- Should be visible in /proc/net/vlan/eth0.300


If you have an existing IP (and the link is up) on the VLAN device, ip.sh works fine:

 [root@molly ~]# ip link set eth0.300 up
 [root@molly ~]# OCF_RESKEY_address="172.31.31.3/24" /usr/share/cluster/ip.sh
             start
 <debug>  Link for eth0.300: Detected
 <info>   Adding IPv4 address 172.31.31.3/24 to eth0.300
 <debug>  Sending gratuitous ARP: 172.31.31.3 54:52:00:06:f7:66 brd
          ff:ff:ff:ff:ff:ff
 rdisc: no process killed
 [root@molly ~]# ip addr list eth0.300
 6: eth0.300@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue 
     link/ether 54:52:00:06:f7:66 brd ff:ff:ff:ff:ff:ff
     inet 172.31.31.2/24 scope global eth0.300
     inet 172.31.31.3/24 scope global secondary eth0.300
     inet6 fe80::5652:ff:fe06:f766/64 scope link 
        valid_lft forever preferred_lft forever

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