how to see the log of dropped packets from iptables

[aaaa2209]

Hello. I am not sure if this is possible. I apply "iptables -I INPUT -s a.b.c.d -j DROP" rules for many IP to block attackers. The Centos server is doing fine. I am curios if I can see the log of the firewall when it applies the rule. Like it tells me the IP a.b.c.d try to scan and sign in with a wrong password, and the firewall drops the packet.
Thank you. Let me know if you need more information.

Regards,
Jack

[TrevorH]

Create a new chain, called say LOGDROP and in that chain you have two rules, the first -j LOG and the second -j DROP. Then instead of using -j DROP on your original rule, you change it to -j LOGDROP.

[BShT]

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