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I have created a VM in XenServer and I'm trying to assign three IPs (local and public) to it. Now as i read from google that I can create three files like ifcfg-eth0, ifcfg-eth0:0 and ifcfg-eth0:1 and change IPs in those files accordingly.

but my questions are:

  1. If I create files with name ifcfg-eth0, ifcfg-eth1 and ifcfg-eth2, does it mean the same?
  2. In Xencenter, I'm unable to see 3 IP's assigned to my VM but when I try to connect to my VM then I'm able to connect to it using different IPs... so what can be the issue with that?
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up vote 1 down vote accepted

Multiple IP addresses is not the same thing as multiple interfaces. Typically a single interface represents a single L2 network but can have multiple IP addresses (sometimes known as aliases or secondaries). Multiple interfaces, in turn, generally correspond to distinct L2 networks.

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However, common network configuration scripts make it difficult to have multiple IPs on one interface (whether you have one or many). I had to write my own new script in just to get it to work in Ubuntu. – Skaperen Aug 16 '12 at 23:53
It shouldn't be - just set up the /etc/network/interfaces file for eth0:0, eth0:1, etc for each alias as if it were a separate interface. – rnxrx Aug 16 '12 at 23:56
The scripts assume eth0:0 and eth0:1 are separate physical interfaces. This results in servers being taken down and started back up for each of these. – Skaperen Aug 17 '12 at 3:57
Yeah - that is annoying behavior. Same situation with VLAN interfaces. – rnxrx Aug 17 '12 at 4:02

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