[ale] SSH Woes
transam at verysecurelinux.com
Fri Apr 22 01:46:20 EDT 2005
On Thu, Apr 21, 2005 at 10:43:11AM -0400, Michael B. Trausch wrote:
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> Does anyone here know of issues with 2.6.x.x kernels and long-term SSH
> I know that if I SSH into my system with 126.96.36.199, the connection seems
> to randomly crap out. If I do so to 2.4.29 or 2.4.30, it doesn't.
> This happens directly on the same subnet, as well as over the Internet
> with nothing between.
It happening on the same subnet rules out braindamaged firewalls.
First, try doing:
to see what your TCP keepalive time is under each kernel. If it is much
longer under your 2.6 kernel, try adding:
# Bob: Shorten for SSH through finicky firewalls (default is 7200 secs):
echo "Set TCP keepalive time to 180 seconds"
echo 180 > /proc/sys/net/ipv4/tcp_keepalive_time
to your /etc/rc.d/rc.local file and rebooting.
Please let me know if that is the problem.
> - --
> Michael B. Trausch <fd0man at gmail.com>
> Website: http://fd0man.chadeux.net/ Jabber: mtrausch at jabber.com
> Phone: +1-(678)-522-7934 FAX (US Only): 1-866-806-4647
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Bob Toxen, CTO
Fly-By-Day Consulting, Inc.
d/b/a Horizon Network Security
"Your expert in Firewalls, Virus and Spam Filters, VPNs,
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