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Old 02-07-2012, 06:57 AM   #1
amartlk
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blocking port


Hi

I have centos 5.3 installed i blocked the port 4444 but when i checked the status of port it shows --
4444/tcp filtered krb524
what it means should it blocked or not and what is krb524


AMAR
 
Old 02-07-2012, 07:26 AM   #2
acid_kewpie
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it means no response was recieved: There is nothing there OR your firewall is droppping the requests to pretend there is nothing there.

and krb524: http://www.google.com/search?q=krb524 But regardless of what it is, it looks like you've just picked this port at "random" and krb524, by convention, uses that port on other systems. Ignore it.

Last edited by acid_kewpie; 02-07-2012 at 07:27 AM.
 
Old 02-07-2012, 08:05 AM   #3
amartlk
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Thanks for response
it means that port 4444 is blocked ?


AMar
 
Old 02-07-2012, 08:12 AM   #4
acid_kewpie
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Quote:
Originally Posted by amartlk View Post
Thanks for response
it means that port 4444 is blocked ?


AMar
no, it doesn't. It means, as I said, that nothing came back. an iptables rule COULD cause this, which would be a block, but maybe there's just nothing listening in the first place.
 
Old 02-07-2012, 08:43 AM   #5
amartlk
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Hi
Actually i want to block port 4444 in my server hence i use the following rule

iptables -A INPUT -p tcp --destination-port 4444 -j DROP
iptables -A OUTPUT -p tcp --destination-port 4444 -j DROP
iptables -A INPUT -p tcp --destination-port 4444 -j DROP
iptables -A OUTPUT -p tcp --destination-port 4444 -j DROP
iptables -A INPUT -p udp --destination-port 4444 -j DROP
iptables -A OUTPUT -p udp --destination-port 4444 -j DROP
iptables -A INPUT -p udp --destination-port 4444 -j DROP
iptables -A OUTPUT -p udp --destination-port 4444 -j DROP

but the application which use port 4444 is still running

while the status of port showing is 4444/tcp filtered krb524



AMAr
 
Old 02-07-2012, 08:52 AM   #6
acid_kewpie
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So yea, looks like that is blocked. But wtf have you got the same pair of rules 4 times?? There's also no need for an "OUTPUT" rule at all.
 
Old 02-09-2012, 01:19 AM   #7
amartlk
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Thanks!!!
 
  


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