From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: autofs no_local_binds option (nfs <-> bind mounts) Date: Tue, 13 Jan 2004 12:54:49 -0800 Sender: autofs-bounces@linux.kernel.org Message-ID: <40045B19.2040301@zytor.com> References: <200401132042.i0DKgDR0001085265@anw.zk3.dec.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200401132042.i0DKgDR0001085265@anw.zk3.dec.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: autofs-bounces@linux.kernel.org Content-Type: text/plain; charset="us-ascii" To: Eric Werme USG Cc: autofs@linux.kernel.org, alexander.marx@hp.com Eric Werme USG wrote: > > *the same system* as the server? I don't know much about Linux internals, > one reason I don't post here often, but I try to offer insight to other > systems. Tru64 Unix has a lot of BSD heritage. If mailhub1 is providing the > mailhub service and mounts something from mailhub, messages sent to mailhub > will be caught in the routing code and directed to the loopback "NIC" lo0. > If the mailhub service (IP address) is relocated to mailhub2, the routing > code will see that no NIC on mailhub1 has the mailhub IP address and will > give the message to a NIC that can reach it. (And ARP resolves the MAC > address and it all runs like a normal remote mount.) > That one is not a problem. The problem is that you either need to force the local address of the mount explicitly at the application layer (in this case this would require a localaddr= option to mount, or something similar) or it needs to be done by setting up the appropriate rules in the kernel. > Ah. Back to automount/autofs. I made many fixes to Sun's old automount, > one of them was to rummage among all the NICs looking to see if the > FS was really a local mount and provide the appropriate symlink. The > cluster folks didn't realize I also checked the alias addresses too, > so I had to add an option to disable that to force a real NFS call. > > You mention "you can't just move the IP address away," is that something > Linux doesn't support yet? No problem on Tru64. A NIC has one permanent > address and a bunch of aliases that can come and go at the whims of the > admins or load balancing software: No, the problem is: which local address will the socket be bound to. -hpa