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2.8 stops routing when portscanning through it
- To: misc_(_at_)_openbsd_(_dot_)_org
- Subject: 2.8 stops routing when portscanning through it
- From: Sebastian Stark <seb_(_at_)_todesplanet_(_dot_)_de>
- Date: Mon, 14 May 2001 19:41:39 +0200
- Mail-followup-to: misc_(_at_)_openbsd_(_dot_)_org
I'm having a problem with 2.8-stable. This 2.8 box acts as a router
for my small network (3 clients) and uses PPPoE/DSL for the internet
Now, if I start some parallel nmap scans from a *client* box, after
a while, the 2.8 box will stop routing. Ping time in the LAN will
become >1sec which is not acceptable. Pings from clients outside
get lost. But I can still logon with ssh (slow!).
Then, already logged into the router, I kill the nmaps on the client.
Trying to ping some host outside I get "No buffer space available".
After a short while (3min) pings from client to router are like that:
64 bytes from 192.168.1.111: icmp_seq=36 ttl=255 time=827.4 ms
64 bytes from 192.168.1.111: icmp_seq=37 ttl=255 time=0.5 ms
64 bytes from 192.168.1.111: icmp_seq=38 ttl=255 time=14082.0 ms
64 bytes from 192.168.1.111: icmp_seq=53 ttl=255 time=7717.3 ms
64 bytes from 192.168.1.111: icmp_seq=61 ttl=255 time=0.5 ms
The box is nearly dead.
Another 3 minutes later, all is working again.
1) is this a problem with pppoe?
2) how can I flush the buffer space?
3) can I get around this problem?
(No, I'm not a hacker, I do scans for customers.)
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