Multihoming SGI Octane 6.3 w/ Different subnets & single NIC

[captinsk]

Hello gurus,

First, I'm *very* new to this SGI Octane computer & IRIX v6.3. So if this seems like a moot issue, please understand that I'm near clueless and a newbie.

What I want to do is add a second ip address from a different network to the existing interface. I don't want to change the host name or existing ip because when I do, I have a bunch of applications & licensing that break.

I can get as far as pinging the SGI from a remote workstation on the new network, but I can't ping the remote wkstn from the SGI.

Done so far:
1. I added an alias via "ifconfig". ie "ifconfig ef0 alias 192.168.0.10 netmask 0xffffff00 broadcast 192.168.0.255"
2. I do route adds via "route". ie 1. "route add default 192.168.0.1"

When I do a "ifconfig -v", I get both addresses on the nic.

I'll post a routing table config in a second post.

tin,
Steve

 

[captinsk]

Routing Info

mycomp (primary) = 192.168.10.2, 0xffffff00
sgic(2nd logical)= 192.168.100.2, 0xffffff00

gw = gateway

Destination, Gateway, Netmask, FLAGS,Interface

localhost, localhost, , UH, lo0
192.168.10, link#1, 0xffffff00, UC, ef0
mycomp, localhost, , UGHS, lo0
192.168.100, link#1, 0xffffff00, UC, ef0
gw, 0:80:c8:b4:82:87, , UHLW, ef0
sgic, 8:0:69:13:2C:a9, , UHLW, lo0
<224.* addressing has been omitted>
255.255.255.255, 192.168.10.255, UGHS, ef0

 

[crimso]

maybe i'm the rookie but i'm confused....you have in your first post a 192.168.0.10 but then mycomp and sgic are different yet. i also notice in the second post that your netstat doesn't have the default destination. can you repost an ifconfig -av and a netstat -rn please??

 

[captinsk]

Sorry crimso,

It would appear my sanitization process overlooked some things. Thank you for responding!

Supppose the gateway for the primary configuration is
192.168.10.1 with a mask of 0xffffff00. The SGI's ip address for this network is 192.168.10.2

And suppose the gateway for the second ip address is 192.168.100.1 with a mask of 0xffffff00.The SGI's ip address for this network is 192.168.100.2

I &quot;add/change&quot; the default route to be the gateway of the second ip address setup, that is to say, 192.168.100.1.

ifconfig -av:

ef0: flags=8415c43<UP,BROADCAST,RUNNING,FILTMULTI,MULTICAST,CKSUM,DRVLOCK,LINK0,IPALIAS,IPV6>
inet 192.168.10.2 netmask 0xffffff00 broadcast 192.168.10.255
inet 192.168.100.2 netmask 0xffffff00 broadcast 192.168.100.255

lo0: flags=8001849<UP,LOOPBACK,RUN,MULTI,CKSUM,IPV6>
inet 127.0.0.1 netmask 0xff000000

netstat -rn
Destination, Gateway, Netmask, FLAGS,Interface

default, 192.168.100.1,,UGS,ef0
127.0.0.1, 127.0.0.1, , UH, lo0
192.168.10, link#1, 0xffffff00, UC, ef0
mycomp, localhost, , UGHS, lo0
192.168.100, link#1, 0xffffff00, UC, ef0
gw, 0:80:c8:b4:82:87, , UHLW, ef0
sgic, 8:0:69:13:2C:a9, , UHLW, lo0
<224.* addressing has been omitted>
255.255.255.255, 192.168.10.255, UGHS, ef0

 

[captinsk]

In case you're wondering, I've tried changnig the broadcast address to match that of the second network.

 

[crimso]

which subnet is the remote workstation on? when you posted the netstat it looks as though you omitted the n as one of the options. the reason for -rn is netstat will return ip #'s and not hostname resolutions. in my experience with these situations you're better off with a default gateway that is on the primary hostnames interface (.10.1 in your case). you could then add a static route to the .100 segment (the aliased segment); &quot;route add -net 192.168.100 192.168.10.1&quot;. this should work assuming that the gateway 10.1 knows how to route the traffic. if you're only going to one machine on the .100 segment you could add a static route to a host instead. without knowing the exact topology of your site i'm kinda guessing. have you considered using the routing daemon? i hate to say it but sun's have notoriously done this stuff better and made it easier but it is possible with sgi's too.

 

[captinsk]

Thanks for your response, crimso.

The &quot;real&quot; network is actually on the second address.
The network for the primary address doesn't exist.

The licensing which I was trying to maintan is tied to the primary ip & hostname.

Fortunately, there were some other issues with the licensing which forced the issue in being corrected.

So unfortunately, my multihoming issue has become a curiosity rather than a necessity.

It's unfortunate that it wasn't a simple case of adding the network ip, mask, & gateway. When I have more time I'll revisit the issue.

Thanks for trying to make sense of this crimso.

cheers,
Steve

 

[crimso]

it actually is as simple as you described but you need to get your router/switch people involved. we used to do it here all the time to 'bridge' gaps between subnets. it really has a small niche now though. especially when dealing with 'inside' vlans and 'outside' ones. switching and routing protocols have pretty much made doing it redundant. best regards.