Block an IP address from connecting to a server

iptables -A INPUT -s 222.35.138.25/32 -j DROP
This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

10
By: root
2009-02-02 12:42:04

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What Others Think

exactly what I needed to get ridd of several IP addresses.
kille · 485 weeks and 5 days ago
I usually use "-I INPUT" rather than "-A INPUT" to ensure it's not allowed by something else first. Also is the /32 required?
pixelbeat · 485 weeks and 2 days ago
I'd really like to shut this off now that I've tested it. How might I go about that?
Tralce · 480 weeks and 1 day ago
Check first. iptables -vn -L INPUT Add rule. iptables -A INPUT -s 222.35.138.25/32 -j DROP Check that it's there. Remove rule. iptables -D INPUT -s 222.34.138.25/32 -j DROP And then check again that it's gone.
AJxn · 344 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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