Re: IPNAT seems to affect network performance? of jails on lo0 (10.0.0.0/24) - why?
I know that ssh does a reverse dns lookup of the ip you connect from - no matter if its local or not. On Tue, Jun 26, 2012 at 4:58 PM, Christopher J. Ruwe wrote: > On Mon, 25 Jun 2012 18:23:56 -0400 > Robert Huff wrote: > >> >> Christopher J. Ruwe writes: >> >> > On a KVM virtualized host, I run FreeBSD 8.3-RELEASE-p3 and some >> > qjails, 8.3-RELEASE. The jails are connected all via lo0 on >> > 10.0.0.0. >> > >> > While by the large working as expected, I have noticed one >> > pecularity I have failed to pinpoint: When launching processes >> > with some network interaction, like sshing into one of the jails >> > from the platform or launching emacs, the command spends ages ( >> > ~(1-2) minutes) idling? (nothing happens) before becoming >> > interactive. >> >> If the number is very close to 90 seconds, my first guess >> would be you have a DNS problem. >> >> >> Robert Huff >> >> ___ >> freebsd-questions@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-questions >> To unsubscribe, send any mail to >> "freebsd-questions-unsubscr...@freebsd.org" > > Thanks for the hint. It was DNS ... I have copied a resolv.conf into the > jails for future use, but did not enable NAT from the start. > > The issue disappeared when I commented out the nameserver entries and > switched NAT off again, i.e., I could login using ssh in a matter of > seconds, not minutes. > > Now to the followup: Why does ssh and emacs! require DNS for entirely local > connections or just to be started? > > Anyway, thanks for that hint, cheers, > -- > Christopher > TZ: GMT + 2h -- Med Venlig Hilsen Kalle R. Møller ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: IPNAT seems to affect network performance? of jails on lo0 (10.0.0.0/24) - why?
On Mon, 25 Jun 2012 18:23:56 -0400 Robert Huff wrote: > > Christopher J. Ruwe writes: > > > On a KVM virtualized host, I run FreeBSD 8.3-RELEASE-p3 and some > > qjails, 8.3-RELEASE. The jails are connected all via lo0 on > > 10.0.0.0. > > > > While by the large working as expected, I have noticed one > > pecularity I have failed to pinpoint: When launching processes > > with some network interaction, like sshing into one of the jails > > from the platform or launching emacs, the command spends ages ( > > ~(1-2) minutes) idling? (nothing happens) before becoming > > interactive. > > If the number is very close to 90 seconds, my first guess > would be you have a DNS problem. > > > Robert Huff > > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to > "freebsd-questions-unsubscr...@freebsd.org" Thanks for the hint. It was DNS ... I have copied a resolv.conf into the jails for future use, but did not enable NAT from the start. The issue disappeared when I commented out the nameserver entries and switched NAT off again, i.e., I could login using ssh in a matter of seconds, not minutes. Now to the followup: Why does ssh and emacs! require DNS for entirely local connections or just to be started? Anyway, thanks for that hint, cheers, -- Christopher TZ: GMT + 2h signature.asc Description: PGP signature
IPNAT seems to affect network performance? of jails on lo0 (10.0.0.0/24) - why?
Christopher J. Ruwe writes: > On a KVM virtualized host, I run FreeBSD 8.3-RELEASE-p3 and some > qjails, 8.3-RELEASE. The jails are connected all via lo0 on > 10.0.0.0. > > While by the large working as expected, I have noticed one > pecularity I have failed to pinpoint: When launching processes > with some network interaction, like sshing into one of the jails > from the platform or launching emacs, the command spends ages ( > ~(1-2) minutes) idling? (nothing happens) before becoming > interactive. If the number is very close to 90 seconds, my first guess would be you have a DNS problem. Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
IPNAT seems to affect network performance? of jails on lo0 (10.0.0.0/24) - why?
On a KVM virtualized host, I run FreeBSD 8.3-RELEASE-p3 and some qjails, 8.3-RELEASE. The jails are connected all via lo0 on 10.0.0.0. While by the large working as expected, I have noticed one pecularity I have failed to pinpoint: When launching processes with some network interaction, like sshing into one of the jails from the platform or launching emacs, the command spends ages ( ~(1-2) minutes) idling? (nothing happens) before becoming interactive. For reasons unreleated, I have enabled NAT with ipf for the jails on 10.0.0.0/24 (to the external re0 IF and some IP) and, out of the blue, logging into the jails or starting emacs became snappy again. Why? Why does ipnatting jails which should be connected via the same lo0 on 10.0.0.0 have any impact? Don't get me wrong, I am not complaining and it solved an issue which gave me kind of headaches, but I would like to understand. Thanks and cheers, -- Christopher TZ: GMT + 2h signature.asc Description: PGP signature
