pfSense

Sorry, affected version is 2.1

I have tested now again and saw that problem resource is if CARP Ip is defined after IP Alias (order priority problem), the carp_status.php gives the below error.

Oct 9 03:51:18 pf php: /carp_status.php: The command '/sbin/ifconfig '' inet '192.168.1.20'/'24' alias' returned exit code '1', the output was 'ifconfig: interface does not exist

How to reproduce this:
I ran into this bug when I modified a setup pulled in from PFSense 2.0.x that looked like this:
(13 PARP VIPs bound to WAN)
(2 CARP VIPs, LAN and WAN)
(2 PARP VIPs, bound to WAN)

I edited/transformed the PARPs into IPAlias VIPs bound to the CARP WAN gateway, and then had a VIP list that looked like this:
(13 IPAlias VIPs, bound to CARP WANgw)
(2 CARP VIPs, LAN and WAN -- unchanged from 2.0.x)
(2 IPAlias VIPs, bound to CARP WANgw)

The result was that two of my IPaliases worked, and 13 did not bind to the CARP VIP, probably because of the reason Atif mentioned above.

If I create a new CARP alias, it's added at the bottom of the VIP list, so getting all CARP VIP interfaces to work correctly would mean deleting and re-adding all of the IPAlias rules!

So this bug hints at two problems:
1. IPaliases can't be declared before a CARP VIP, which isn't really a problem, because the network stack is working as designed...
2. Order in the PFSense VIP list matters to the IPAlias type (possibly others), and either PFSense should order VIPs properly, or allow the user to do so in the GUI interface. Personally, I'd prefer the former.