Suddenly IP aliases don't work from rc file?

[Chris Buechler]

On Sun, Jan 15, 2012 at 7:00 PM,  <up at 3.am> wrote:
> A dedicated server that I rent has a primary IP and 6 alias IPs.  Everything was
> working ok with the rc.conf configured like this:
>
> ifconfig_rl0="inet primary.ip.address netmask 255.255.254.0"
>
> The primary IP above comes up fine.  I then have:
>
> ifconfig_rl0_alias0="inet second.ip.addr netmask 255.255.255.255"
> ifconfig_rl0_alias1="inet third.ip.addr netmask 255.255.255.255"
>
> and so on.  This worked fine until we had an Ethernet card go bad.  It was
> replaced and I had to use a different driver, but none of the alias IPs worked.
> They showed up in ifconfig, but they couldn't be reached from outside the
> localhost.  So, I had them put in an identical Realtek s before, change the driver
> back as above but the problem persisted.
>
> I tried moving the ifconfig lines from the end of the rc file to near the
> beginning, right after the main IP ifconfig, but still no go after rebooting each
> time.  I messed around with this for a while and finally just removed the alias
> IPs using the manual "ifconfig rl0 second.ip.addr netmask 255.255.255.255 -alias"
> and re-adding it the same way.  That got those IPs working again.
>
> The only thing I can think of is that this server does have an onboard Attansic
> Ether that the GENERIC kernel sees...we actually used it yesterday after the first
> Realtek died and it worked fine for a while, then would just crap out
> intermittently.  We went back to Realtek and that fixed the connection crappiness,
> but that's when the alias problems began...all I had done was change the driver
> letters.  One thing that makes me wonder about the other Ether is that "netstat
> -rn showed "link#2" for the alias IPs.  However, it still shows that after
> deleting and re-adding them, which fixed it.
>
> Any ideas?  It's working now but any kind of reboot is going to cause havoc.

Are you sure it's the reboot that causes havoc? Sounds like you may
have been fighting an ARP cache upstream that either timed out or got
updated in the process of mucking around with the IPs. I also wouldn't
touch a server with Realtek NICs in it, probably the worst NIC
hardware ever built.