Card on router to be replaced, what implications?

[Alan Casey]

I have a HP N-Class server which is connected to a router on our network, the card that it connects to on the router will be replaced tonight.

I would like to know if I will need to reboot the N-Class server, or if the new network card will be picked up automatically by the server, or after a certain timeout period.

What I am worried about is that changing the card on the router will affectively change the route to the network, and that the server will not pick this up automatically.

thanks,
alan

[Alan Casey]

Thanks but,

It's the card on the router that is being replaced, not the card on the HP server.

[Paula J Frazer-Campbell · Accepted solution]

Alan

There should be no problems, but back up the routing table on the router first.

The server will not require a reboot - it is the same as adding a new router.

Paula

[harry d brown jr]

The best way is to Shutdown the server, replace the card, boot the server, and then have someone in networking flush the arp tables in the router because your mac address will change.

live free or die
harry

[Ron Kinner]

Paula is correct. You should not have to reboot the server and the arp table entry should expire before the new card comes back on line as long as you have not previously permanently installed the MAC of the router in your arp table with arp -s. You can check it with arp -a and look to see if the router is in the table. Then after the card has been changed if you repeat arp -a and get the same MAC for the router simply issue
arp -d routername
and that will remove it and force the HPUX to send out an ARP for the MAC of the router's IP address the next time it needs to send something to the router.

You might also check that your switch does not have a static entry for the router's old MAC address tho this shouldn't hurt anything. It is also possible to tell a switch that only a certain MAC address can use a certain port and if this has been done it would cause problems.

I assume your router guy is not changing the IP address of the router at the same time as he changes the card. If he does, strangle him! ;-)

Ron