Unix newbie

[Fßbio]

Hello,


I'm an Unix newbie and I'm having problems with my HP-UX 10.20 server, because everytime that my link with my brach goes down some strange routes appears in my server (netstat -r) and I have to delete them because nothing works (route delete xxxx). I tried the netconf, but GATED=0 and RDPD=0, so my server doesn't have any dynamic route enable and on my init.d directory I haven't see anything that could be my problem (See attached file).


Please, someone have any idea about what could be my problem?

[Rick Garland]

An application or the router is adding the routes.

[Victor BERRIDGE]

start by checking your IP and put it right:
/etc/ifconfig lan0 inet netmask up
check with netstat -r
then /etc/route ass default < route addr> 1
again netstat -r
if it works, go and correct your file /etc/rc.config.d/netconf

[John Palmer]

There have been some recent discussions on this topic. If you click SEARCH and select the forums for ICMP you will find some interesting threads.

Regards,
John

[Mark Mitchell]

I have seen this a long time ago, I did a route dump and created the defaults in one entry. This problem hasn't reoccured yet. Do some reseach on your network setting and these commands. This will affect current users so doing it off hours is recommended. The first part dumps your tables, so know what your default is and your loopback address is. When this is recreated you won't see multiple entries anymore for every user. This is an example of the commands of a server at 198.20.1.3 to give you an idea of what you are looking for.
route table dump
route -f
route add default 198.20.1.2
rout add 127.0.0.1 127.0.0.1
route add 198.20.1.3 127.0.0.1

[Anthony deRito]

Fabio, you have had replies to this issue on a recent post. have you not read the replies?

Your routes are being created dynamically by your router(s). If your primary link is unable to direct the packet to its destination, then it will send an ICMP Redirect to your UNIX box and specify an alternate gateway for the packet. This alternate gateway may not be valid but UNIX does not care. All it knows is that it recevied an ICMP Redirect from the primary router. You can turn off ICMP Redirects on your router if you would like.

netstat -nr will show you the routing table. Check out what gateways are specified for the devices you are having trouble with. You can delete the entry with:

route delete net|host destination

You can add an entry with:

route add net|host destination 1

The 1 at the end defines this entry to be a gateway and sets the UG flags

Also, check out the man pages on route and routing.

Tony

[Anthony deRito · Accepted solution]

Fabio, the RPDP and GATED variables have nothing to do with the system learning dynamic routes. This is that way routing works on UNIX. You may want to also get into your router and run the following EXEC command:

show ip route

and check if the default routes are correct. Specifically the entry with the * near it.

Tony