Solaris 8 ifconfig (lo0) problem VS Solaris 2.5,2.6,7

Solaris 8 ifconfig (lo0) problem VS Solaris 2.5,2.6,7

Post by Shaw » Sat, 03 Mar 2001 12:04:11



Under all versions of Solaris, except 8, when you ifconfig your loopback
address (lo0) with an IP address of some other host that host won't be able to
ping or make any network connections to the server.  That's obvious because the
ip address is now local to the machine and everything just breaks for that
host.

HOST = 10.20.20.200/24
Some router in between to connect each other.
Server = 10.2.0.2/24

Then you "ifconfig lo0:1 10.20.20.200 netmask 255.255.255.255 up" and the host
cannot talk to the server anymore.

In the Solaris 8 environment, even patched up with xref file 2/28/01, when you
do an "ifconfig lo0 addif 10.20.20.200 netmask 255.255.255.255 up" or "ifconfig
lo0:1 plumb ; ifconfig lo0:1 10.20.20.200 netmask 255.255.255.255 up" the host
is still able to talk with the server.  If you wait like 2 hours, sometimes the
host will not be able to ping/talk to the server until you unplumb lo0:1 then
traffic will start right away.

Has anyone else seen this?  Is this an "added feature" in solaris 8?  Any
suggestions to make it work like previous versions of Solaris.  Well for that
matter make it would like is should.   :)

-- Shawn

 
 
 

Solaris 8 ifconfig (lo0) problem VS Solaris 2.5,2.6,7

Post by Darren Dunha » Sun, 04 Mar 2001 04:10:10



> Under all versions of Solaris, except 8, when you ifconfig your loopback
> address (lo0) with an IP address of some other host that host won't be able to
> ping or make any network connections to the server.  That's obvious because the
> ip address is now local to the machine and everything just breaks for that
> host.
> HOST = 10.20.20.200/24
> Some router in between to connect each other.
> Server = 10.2.0.2/24
> Then you "ifconfig lo0:1 10.20.20.200 netmask 255.255.255.255 up" and the host
> cannot talk to the server anymore.
> In the Solaris 8 environment, even patched up with xref file 2/28/01, when you
> do an "ifconfig lo0 addif 10.20.20.200 netmask 255.255.255.255 up" or "ifconfig
> lo0:1 plumb ; ifconfig lo0:1 10.20.20.200 netmask 255.255.255.255 up" the host
> is still able to talk with the server.  If you wait like 2 hours, sometimes the
> host will not be able to ping/talk to the server until you unplumb lo0:1 then
> traffic will start right away.
> Has anyone else seen this?  Is this an "added feature" in solaris 8?  Any
> suggestions to make it work like previous versions of Solaris.  Well for that
> matter make it would like is should.   :)

What does the routing table look like immediately after the ifconfig on
both machines?  Does 7 add an entry, while 8 doesn't?  If that's all it
is, you can probably add a static route.  In fact, you could probably
add a host route *instead* of doing the ifconfig if you're just trying
to not be able to transmit to a machine.

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