[lug] SSH slows to a crawl

[Chip Atkinson]

There could be a bad switch or cable causing problems?  Perhaps
wireshark or tcpdump to see if there are a lot of packet resends.

You could also check if there are iptables rules that limit traffic.

Chip
On Tue, 29 Sep 2009, Gordon Golding wrote:

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> SSH on 2
> out of 3 linux FC11 servers has slowed to a crawl.
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> 
> 
> ?
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> We have 3
> Linux servers all plugged into the same hub.
> 
> 
> 
> ?
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> Yesterday,
> they were all fast with ssh and other connections.
> 
> 
> 
> ?
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> Today, 2
> out of the 3 suddenly have very very slow ssh connection speeds, taking seconds
> to respond.? But other connections are not slow.
> 
> 
> 
> ?
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> Any combination ssh connection involving a Slow server is slow.
> 
> BUT -
> 
> 
> If you ping
> the slow ones from in the room (same hub) or out of the room, through a switch, ping is fast:?
> 0.180 ms or 0.284 ms, for example.
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> 
> Other things like HTTP seem just fine, too.
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> Looking at
> /var/log/secure, I see no attempted connections.
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> SELinux has been disabled.? No effect.
> 
>  CPU is only at 0.3 usage.
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> 
> 
> ?
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> Thoughts?
> 
> 
> Gordon 
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>