On Fri, May 20, 2016, Jan Bramkamp wrote: > On 20/05/16 15:51, Vladimir Zakharov wrote: > > On Fri, May 20, 2016, Jan Bramkamp wrote: > >> On 20/05/16 14:54, Vladimir Zakharov wrote: > >>> Hello > >>> > >>> On Fri, May 20, 2016, O. Hartmann wrote: > >>>> I reported earlier about broken pipes in ssh sessions to remote hosts, > >>>> which occur on an erratic basis. i'm investigating this problem now and > >>>> it seems that it is also ipfw-related, but I'm not sure. This problem > >>>> is present since a couple of weeks now. > >>> > >>> Maybe this could help... > >>> > >>> I've also experienced problems with broken pipes in ssh sessions some > >>> time ago. Setting in sysctl.conf > >>> > >>> net.inet.ip.fw.dyn_ack_lifetime=3600 > >>> > >>> fixed problem for me. I didn't experiment with the value though. So, > >>> possibly, changing default value (300s) to 1 hour is overkill :). > >> > >> By default the OpenSSH SSH client is configured to use TCP keepalives. > >> Those should produce enough packets at a short enough interval to keep > >> the dynamic IPFW state established. > >> > >> Does your traffic pass through libalias? > > I guess not. How can I be sure? > > Libalias is used by ipfw and the old userland natd to implement IPv4 > NAT. It requires unmodified access to all packets including their > headers. LRO and TSO coalesce packets to reduce save CPU time but the > process is loses some of the information required by libalias. Unless > your ruleset uses ipfw in-kernel NAT or diverts traffic to natd you > don't have to worry about libalias. > > Use `kldstat -v | grep libalias` to check for libalias in the running > kernel and `pgrep natd` to search for running natd instances.
Surely, I do not use NAT (and libalias): root@vzakharov:~ # kldstat -v | grep libalias root@vzakharov:~ # pgrep natd I use GENERIC-NODEBUG kernel (r300138) with ipfw module. And 'workstation' firewall type. -- Regards, | "In theory there is no difference between theory Vladimir Zakharov | and practice. In practice there is."- Yogi Berra _______________________________________________ firstname.lastname@example.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"