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I just bought 10 extra IPs from my host. How do I point these at my CentOS 5 server?

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I assume that is is a question about how to configure the host, not how to route the addresses. – pehrs Apr 11 '10 at 9:09

On CentOS you can use a ifcfg-eth?-range? file to assign multiple IP adresses. For example; you want to assign additional IP adresses to your eth0 interface and you don't have any additional addresses assigned yet. Create the file /etc/sysconfig/network-scripts/ifcfg-eth0-range0:


When you already have assigned additional IP addresses the CLONENUM_START value should match the next available eth0:x number.

If the IP addresses aren't in order you have to create an ifcfg-eth0:x file for each of the addresses. The content should look like this:


Change the DEVICE value to the corresponding filename and run ifup eth0:0 to bring the interface online.

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the IPs are all over the range though, not in order. – ace Apr 11 '10 at 23:00

Use IP aliasing on the host.

ifconfig eth0:1 netmask
ifconfig eth0:2 netmask

To do it permanently you will have to use the files in /etc/sysconfig/network-scripts/ifcfg-<interface>

And so on. But why do you need multiple IPs for a single host? SSL/TLS?

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Check the answer from PowerSp00n for how to setup the ifcfg files. – pehrs Apr 11 '10 at 12:41
multiple IPs for SEO benefit. Hosting a lot of sites that link together on the same server, but want the benefit of the search engine thinking they are on different servers. – ace Apr 11 '10 at 23:01

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