SYN flood! From juniper firewall...how to fix it.

Hi ,
My firewall ISG1000 is keep sending SYN Flood to my log server when I enable the logs...is there any explanation to what happened and how to fix it?
besmile4everAsked:
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yuliang11Commented:
is the IP that is doing the syn flood the management IP address or is it a NAT ip address of the firewall?

 if it's the management IP address , it's  possible that you have configured a SYN(TCP) log (syslog,eg)  to the log server but the log server is maybe running in UDP syslog or something like that. You will see a lot of SYN with no 3 way handkshake as there are no real ports being opened on the log server.
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yuliang11Commented:
if i'm not wrong , isg 1000 has the option to use TCP or UDP syslog. maybe u can try the UDP syslog
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besmile4everAuthor Commented:
ok..how can I set the UDP syslog?
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besmile4everAuthor Commented:
when I enable it on port 514 from the GUI and choosing only event log and traffic log..it still keep sending on TCP...
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yuliang11Commented:
could you print screen and send to yuliang11@yahoo.com ?

tq
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besmile4everAuthor Commented:
yep it is sent..


Cheers.
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yuliang11Commented:
cool ,

 looks like the source IP address is malicious. It's very normal to get these connection from the internet. they are probably some automated worm or script kiddes or hackers trying to get hold of vulnerable application using port 9000 on the internet. You are pretty safe if you are not running TCP 9000 on the internet.

I would suggest these

1. Ignore it

2. If there are too much logs, i suggest blocking the source IP address


As you can see this IP address is already blacklisted in a lot of sites


http://www.mxtoolbox.com/SuperTool.aspx?action=blacklist%3a125.45.109.196


cheers
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besmile4everAuthor Commented:
Many thnks..excellent response.
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