Can i safely block all ports on my sever

Posted by Saif Bechan on Server Fault See other posts from Server Fault or by Saif Bechan
Published on 2010-03-23T04:42:39Z Indexed on 2010/03/23 4:51 UTC
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port

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blocking

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iptables

I have a web server running pleks and get attacked a lot every day. I configured a firewall, and there are some predefined services such as www, and ftp, etc.

I am planning to block all the ports except for the www port and the PLESK port. When I need ftp or ssh access for example i will open the ports in PLESK and then start to work.

Is this a good thing to do or are there some downsides on doing this.

There are some ports I am not sure of, such as SMTP,POP3,IMAP, DNS. Can i close these ports or is there no need to do so.

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