Upgrade NIC without reboot/restart scripts

[Karthik S S]

Hi,

Assuming that we have two NICs in our system one 10MBPS which is configure with an IP address and another 100MBPS without any IP. Now how do I migrate the IP to 100MBPS card without rebooting the machine or restarting the network scripts. Meaning that the presently connected users to the system should not get disturbed. Is it possible?

Pl. let me know
Thanks
Karthik

[T G Manikandan]

I dont think you can migrate the //same IP //without a break of communication to the server.

You need to anyway atleast do a restart of the network scripts.


Thanks

[monasingh_1 · Accepted solution]

Connect the network cable to the same subment for 100BT card as well. and then if you give all the commands in a ( ) separated by ; you should be okay. What I mean is ( ifconfig lan0 down; ifconfig lan1 up IP_ADD netmask NET_MASK)

After that you can also do ifconfig lan0 unplumb if you want.

This has been tried and it works fine, no users will even know about the change except the speed if someone is really wanting the speed...
hope this helps..

[rick jones]

If all you are doing is moving the IP from one NIC to another, you can edit the /etc/rc.config.d/netconf file and alter the interface name associated with the IP.

For the rest, you _must_ be on the console... and there _will_ be a short interruption of traffic...

0) use linkloop through the old nic to a remote system, make sure you find one (UX will work) that responds to the "link-level ping" of linkloop.

1) connect the new nic to the same switch as the old NIC, and run the linkloop command with the new NIC's PPA and make sure that you have link-level connectivity through the new NIC.

2) unplumb the old interface with ifconfig

3) run the ifconfig command to assign the IP to the new NIC

4) run a ping command to make sure that communication works at the IP level in addition to the link level.

5) verify that you have edited the /etc/rc.config.d/netconf file correctly or next time you reboot you may not have working networking.

If you can do steps 2 and 3 quickly enough and everything is OK, cusers will notice at most a slight hiccup. Now, if things go wrong... so best to do this when it would be OK if you were to have a longer network outtage

[Sridhar Bhaskarla]

Hi Karthik,

Rick's point is to be noted to make sure you get your 'linkloop' working first before you try to change the IPs.

There is one more thing with 100 speed on HP. We have not seen it working consistently with AUTO negotiation on. So, you will need to set your switch port and the NIC to 100 Full Duplex with Auto off. Setting it after assigning the IP will break the communication by 11 secs. So, I would suggest the following order after you successfully tested your 'linkloop'.

#lanadmin -X 100FD n

(n is the card instance# on 11x for ex., 2 for lan2)

Make sure it is set to 100 Full Dup auto-off

#lanadmin -x n

Write two scripts with two lines each to unplumb one interface and enable the other like

ifconfig lan0 unplumb
ifconfig lan2 10.10.10.10 netmask 255.255.255.0

Reverse the entries in the second script for backout.

Keep a ping session open to the server from another server.

Run the first script. Ping should break and then start again. If not, run the second script to backout the change.

-Sri

[Steven E. Protter]

You can do it without a reboot.

You can do it with a minimal disruption.

If the two cards are on the same switch and the switch doesn't have any configuration issues.

ifconfig lan1 down
ifconfig lan2 ip_of_old_lan netmask_of_old_lan

Some service disruption will occur. In my tests however, most services resume without much of a problem.

SEP

[Karthik S S]

Hi all,

Thanks for the guidance ... it works :-)

Karthik