What are Subnet Mask and Gateway exactly

Posted by Saif Bechan on Server Fault See other posts from Server Fault or by Saif Bechan
Published on 2010-03-29T05:59:44Z Indexed on 2010/03/29 6:03 UTC
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subnet-mask

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gateway

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ip

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what-is

I have a dedicated server with multiple IP adresses. I run them on Plesk but some of the names are confusing me.

One ip has a subnet mask of 225.225.225.192, another has 225.225.225.0. What does this mean and what happens if i change that.

Another thing i got a gateway. What is that and when will that come in handy.

Another thing I see sometimes behind the ip's is /number. For example:

200.20.20.20/24
200.20.20.20/16
200.20.20.20/8

What will these numbers say.

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