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 12:03:54 -0800 Sender: autofs-bounces@linux.kernel.org Message-ID: <40044F2A.9080305@zytor.com> References: <200401131958.i0DJwlV0001078000@anw.zk3.dec.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200401131958.i0DJwlV0001078000@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 stop-gap cluster system in Tru64 Unix did this. Typically pairs > of servers had system names (service names in the jargon) and bound > the IP address to a NIC on one server. When the service was relocated > manually or on a crash, the IP address was moved to a NIC on the other > server. Disks were on a shared SCSI bus, and the file system would also > go through a umount/mount cycle. Note that no changes to DNS' database > are necessary, just an update to clients' arp tables. > > For example, we have systems "mailhub1" and "mailhub2". The service name > "mailhub" is where Email here winds up. I send mail via SMTP to mailhub, and > read it via NFS from mailhub. Normally I don't care which of mailhub1 > and mailhub2 handles it. For the most part they're just servers, but > sometimes there are reasons to login to one or both of those systems. However, this doesn't address the issue of the client being *the same system*, in which case you can't just move the IP address away from it, since local == remote; you can no longer send packets to the server and get a response back. You can do it if you can get the client and the server sides to bind to *different* IP addresses, in which case the current autofs behaviour will correctly see them as being separate and mount NFS. -hpa