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Old 02-22-2005, 10:28 AM   #1
Registered: Dec 2001
Location: Layton, Utah
Distribution: Red Hat 8.0 and Mandrake 9.0
Posts: 85

Rep: Reputation: 15
My postfix box is sending UDP FLOODS!

I am getting this in my alerts from my firewall.

2005-02-22 08:43:33 alert UDP Flood, From to, using protocol UDP (on zone Trust,interface ethernet1) occurred 1 times

This is a RH 9 box running Postfix. Can someone please help me with this?

the RH 9 box is the and not sure where the 3.4 is comming from as we no longer use that subnet


Old 02-22-2005, 07:19 PM   #2
Senior Member
Registered: Mar 2003
Distribution: Fedora
Posts: 3,658

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First, since you're using RH 9 is your system currently patched, as Redhat stopped supporting it almost a year ago?

Second, is there any reason, why this machine would be doing DNS lookups at the address (was the .3.4 host a secondary DNS server or something similar)?

Third, can you post a capture of packets from this machine? From another system on the network use tcpdump -X dst port 53 and host


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