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Drop or block attackers IP with null routes

Terminal - Drop or block attackers IP with null routes
sudo route add xxx.xxx.xxx.xxx gw lo
2009-02-23 19:58:09
Functions: route sudo
Drop or block attackers IP with null routes

Someone might attack on your system. You can drop attacker IP using IPtables. However, you can use route command to null route unwanted traffic. A null route (also called as blackhole route) is a network route or kernel routing table entry that goes nowhere. Matching packets are dropped (ignored) rather than forwarded, acting as a kind of very limited firewall. The act of using null routes is often called blackhole filtering.


There are 4 alternatives - vote for the best!

Terminal - Alternatives

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What others think

I don't understand the down-votes; this command works as advertised. I'd rather use IPTables, personally, but this is a good dirty hack that will, for example, stop a DoS.

Comment by sud0er 352 weeks and 4 days ago

Thanks. Yeah the only downside to this command is that it doesn't save the rule after reboot.

Comment by JackiesJungle 352 weeks and 3 days ago

Your point of view

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