topic Re: logical IP address in Operating System - Linux

logical IP address

bond007 — Sat, 11 Mar 2006 05:31:55 GMT

Hi All,

How to configure an logical IP address for a NIC?

Thanks and Regards,

Bond.

Re: logical IP address

Sivakumar TS — Sat, 11 Mar 2006 07:40:11 GMT

Hi Bond,

If you mean IP alias, then use the following

#ifconfig eth0:0 netmask up

Regards,

Siva.

Re: logical IP address

Sivakumar TS — Sat, 11 Mar 2006 07:41:16 GMT

Check this url ...

http://www.tldp.org/HOWTO/NET3-4-HOWTO-6.html

Hope this helps,

Sivakumar T S

Re: logical IP address

bond007 — Sat, 11 Mar 2006 07:50:14 GMT

Hello SIva,

Thank you for the quick information.

Is it possible to configure the alias IP addrss in different Subnet.

With Regards,

Bond

Re: logical IP address

Alexander Chuzhoy — Sat, 11 Mar 2006 11:15:05 GMT

The IP of logical adapter must be in the same subnet as the actual adapter's IP.

Re: logical IP address

Alexander Chuzhoy — Sat, 11 Mar 2006 11:19:35 GMT

Oh, and by the way to create a permanent logical IP address do the following:
copy the file of adapter (ifcfg-eth0 for example) to ifcfg-eth0:1
edit the new file (i.e. ifcfg-eth0:1).
Change the DEVICE=eth0 to DEVICE=eth0:1
and also change to IPADDR= field so that it'll have the desired address (in the same subnet).

Re: logical IP address

Senthil Prabu.S_1 — Mon, 13 Mar 2006 03:03:46 GMT

Hi Bond,
Configuring logical IP basically defined by your hardware.

So, what is your hardware. And also IP alias is the one used to configure logical IPs.

HTH
Prabu.S

Re: logical IP address

Senthil Prabu.S_1 — Mon, 13 Mar 2006 03:07:56 GMT

Hi again,
Answering your second question, configuring IP alais address in different subnet is possible.

Refer this link to configure it;
http://www.opendarwin.org/en/articles/network_config/ar01s03.html

HTH,
Prabu.S

Re: logical IP address

Senthil Prabu.S_1 — Mon, 13 Mar 2006 03:27:40 GMT

Hi,
to configure IP-alias address in different subnet,

step 1:
#ifconfig eth3:1 10.10.22.33 broadcast 10.10.22.255 netmask 255.255.0.0 up

snippet of ifconfig -a output;

eth3 Link encap:Ethernet HWaddr 00:0A:E4:80:2F:F7
inet addr:10.10.3.12 Bcast:10.10.3.255 Mask:255.255.0.0
inet6 addr: fe80::20a:e4ff:fe80:2ff7/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2712566 errors:0 dropped:0 overruns:0 frame:0
TX packets:2712547 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:268856055 (256.4 Mb) TX bytes:268831610 (256.3 Mb)
Base address:0x24c0 Memory:dd2c0000-dd2e0000

eth3:1 Link encap:Ethernet HWaddr 00:0A:E4:80:2F:F7
inet addr:10.10.22.33 Bcast:10.10.22.255 Mask:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Base address:0x24c0 Memory:dd2c0000-dd2e0000

HTH,
Prabu.S