On Fri, May 01, 2009 at 06:05:15PM -0400, John A. Sullivan III wrote: > On Fri, 2009-05-01 at 23:34 +0200, Herbert Poetzl wrote: > > On Fri, May 01, 2009 at 04:48:12AM -0400, John A. Sullivan III wrote: > > > Hello, all. I'd like to confirm that I understand the way vserver > > > 2.3 is handling localhost and the loopback address. > > > Am I correct to understand that, unlike earlier version, the > > > default kernel compilation makes it safe to use 127.0.0.1 on a > > > guest? That is, each one is uniquely mapped and does not interfere > > > with the host listening in 127.0.0.1? We can thus set our > > > /etc/hosts files to use: 127.0.0.1 localhost localhost.localdomain > > > etc . . .? > > > However, is it also true that daemon bindings to localhost will > > > still be made to the address in /etc/vservers/<guest>/interfaces/0 > > > and will not include 127.0.0.1 unless explicitly bound? > > > I ask because we were delighted to realize we could simplify > > > our zimbra installation by leaving /etc/hosts at 127.0.0.1 > > > for localhost. We then started retrofitting our other servers > > > to do the same. Some of our servers communicate with sshd on > > > 127.0.0.1. We had changed the configuration files to bind them > > > to the non-loopback address, e.g., 192.168.1.10 because of our > > > old understanding of 127.0.0.1. We also changed sshd_config by > > > removing the ListenAddress 192.168.1.10 so that it goes back to > > > the default of binding to all interfaces. > > > This broke those applications. When we do a netstat -tln on the > > > vserver guests, it shows sshd listening only on 192.168.1.10 (as > > > an example) and not 0.0.0.0. > > if you disable the single IP special casing, this > > will change to the expected behaviour ... > Sorry to be showing my ignorance again but what is "single IP special > casing" that I should be disabling? Thanks - John A Linux-VServer context flag, which controls the behaviour in case a single IP is assigned to a guest (which can be optimized by replacing 0.0.0.0 with that single IP, instead of keeping a list to check against) ... http://linux-vserver.org/Capabilities_and_Flags (see nflags, SINGLE_IP) note, that in the kernel config, you can also set the default behaviour (VSERVER_AUTO_SINGLE) which, when enabled does set that flag automatically HTC, Herbert > > > -- > > > John A. Sullivan III > > > Open Source Development Corporation > > > +1 207-985-7880 > > > jsullivan@opensourcedevel.com > > > > > > http://www.spiritualoutreach.com > > > Making Christianity intelligible to secular society > -- > John A. Sullivan III > Open Source Development Corporation > +1 207-985-7880 > jsullivan@opensourcedevel.com > > http://www.spiritualoutreach.com > Making Christianity intelligible to secular society