--On Monday, September 20, 2004 08:56:39 -0500 Ivan Petrovich <laveer AT 
tuphaan.engr.wichita DOT edu> wrote:

> Howdy,
> 
> Here's the problem:
> I mounted a remote file system on a GNU/Linux system using autofs, and
> amdump fails to back up some files on this file system due to
> "Permission denied." I verified that the files which give this error
> are those that have the 'read' permission bit turned off for 'others'.
> 
> I thought about it and thought that it made sense that 'amdump'
> wouldn't be able to read it since it runs as 'amanda', and not root.
> 
> But how is it that amdump is able to read all files in all other file
> systems (as if it were root), including local file systems and
> NFS-mounted (non-autofs) file systems? Though 'Amanda' user is in the
> 'disk' group, but when amanda runs using 'gtar', it does not read the
> raw device ("/dev/???"), so having group access to the raw devices
> shouldn't help, right?
> 
> Besides, it has no problem reading the NFS-mounted (non-autofs) file
> systems either, and NFS-mounted volumes are not owned by group 'disk'.
> 
> So my questions are:
> 1. How exactly does Amanda's client get read access to all files that
> it dumps when it uses 'gtar'?

gtar is called by the runtar wrapper, which is suid root.

> 2. Does any one know why it couldn't read all files on an auto-mounted
> file system?

Your export of the filesystem is evidently mapping root to nobody, so
Amanda can't read all the files.
Depending on the OS on the fileserver, look for options like root= or
no_root_squash  to enable root on the client to be treated as root on
the fileserver.

Frank

> 
> Thanks in advance!
> 
> Ivan
> 



-- 
Frank Smith                                      fsmith AT hoovers DOT com
Sr. Systems Administrator                       Voice: 512-374-4673
Hoover's Online                                   Fax: 512-374-4501