Red Hat Bugzilla – Bug 129311
Direct map support in v4 might break working config
Last modified: 2007-11-30 17:07:03 EST
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.4.2) Gecko/20040301 Description of problem: Strating to support direct maps in version four is of course mostly an enhancement. But since direct maps work differently than on other systems, it might actually break things. This happens if there are other mounts under the same top-level directory. Version-Release number of selected component (if applicable): autofs-4.1.3-9 How reproducible: Always Steps to Reproduce: 1. Enter "/- auto.direct -rw,intr" and "/nfs/vm auto.vm -rw,intr" in auto.master. 2. Enter "/nfs/ipatinga/src ipatinga:/lfs/src" into auto.direct. 3. Enter "cvs lehrter:/lfs/vm/&" into auto.vm. Actual Results: With autofs 3 the direct map is ignored. /nfs/ipatinga/src is not available while /nfs/vm/cvs is. With autofs 4 the direct map is used, and replaces the entire /nfs tree. /nfs/ipatinga/src becomes available, but /nfs/vm/cvs disappears. Additional info: On other systems (Solaris, HP-UX, AIX) both directories are available, since not the whole tree is taken. Adding support for direct mounts certainly is a good thing. Adding it in a different way than used on other systems, is unfortunate, but better than nothing. Applying that change between two update releases is slightly questionable though. We had of course done workarounds on our Linux systems to cater for the lack of support for direct maps. We can certainly figure out some other workaround for the different behaviour in treatment of direct maps in the new version. While I would count on having to do that kind of work for an upgrade to RHEL4, I would not expect it for an upgrade release. An idea would be to have an easy way to disable the direct maps. Then you could choose if you want the new functionality, or prefer it the old way. This could be a switch in /etc/sysconfig/autofs; if the variable is set, the /etc/rc.d/init.d/autofs would skip /- entries in the map. This kind of patch could be kept for the RHEL3U* releases, and removed with RHEL4.
Yes, this point has been bothering me. I put together a new package which disables direct support by default. You can enable it by setting DISABLE_DIRECT=0 in /etc/sysconfig/autofs. Thanks for the report. I will update the bug when the new package is available. -Jeff
I see this is implemented in U3. I'm slightly surprised by the test used. if [ $DISABLE_DIRECT -eq 1 \ -a x`echo $dir | grep -E "^/-"` != 'x' ] Wouldn't it have been simpler and still correct to just say like this? if [ $DISABLE_DIRECT -eq 1 -a x$dir = x/- ] A difference would be that this would not remove a dir of the form "/-xxx". But should that really be removed? Anyway, the delivered fix works, so I close this.