Contents of internals

Internals

Log Messages

In the following sections a brief explanation is given of some of the log messages made by . Where the message is in typewriter font, it corresponds exactly to the message produced by . Words in italic are replaced by an appropriate string. Variables, var, indicate that the value of the appropriate variable is output.

Log messages are either sent direct to a file, or logged via the syslog(3) mechanism. Messages are logged with facility LOG_DAEMON when using syslog(3). In either case, entries in the file are of the form:

date-string hostname amd[pid] message

Fatal errors attempts to deal with unusual events. Whenever it is not possible to deal with such an error, will log an appropriate message and, if it cannot possibly continue, will either exit or abort. These messages are selected by -x fatal on the command line. When syslog(3) is being used, they are logged with level LOG_FATAL. Even if continues to operate it is likely to remain in a precarious state and should be restarted at the earliest opportunity.

Attempting to inherit not-a-filesystem: The prototype mount point created during a filesystem restart did not contain a reference to the restarted filesystem. This erorr ``should never happen''.
Can't bind to domain "yp-domain": A specific YP domain was requested on the command line, but no server for that domain is available on the local net.
Can't determine IP address of this host (hostname): When starts it determines its own IP address. If this lookup fails then cannot continue. The hostname it looks up is that obtained returned by gethostname(2) system call.
Can't find root file handle for automount point: creates its own file handles for the automount points. When it mounts itself as a server, it must pass these file handles to the local kernel. If the filehandle is not obtainable the mount point is ignored. This error ``should never happen''.
Must be root to mount filesystems (euid = euid): To prevent embarrassment, makes sure it has appropriate system privileges. This amounts to having an euid of 0. The check is made after argument processing complete to give non-root users a chance to access the ``-v'' option.
No work to do - quitting: No automount points were given on the command line and so there is no work to do.
Out of memory in realloc: While attempting to realloc some memory, the memory space available to was exhausted. This is an unrecoverable error.
Out of memory: While attempting to malloc some memory, the memory space available to was exhausted. This is an unrecoverable error.
cannot create rpc/udp service: Either the NFS or AMQ endpoint could not be created.
gethostname: description: The gethostname(2) system call failed during startup.
host name is not set: The gethostname(2) system call returned a zero length host name. This can happen if is started in single user mode just after booting the system.
ifs_match called!: An internal error occurred while restarting a pre-mounted filesystem. This error ``should never happen''.
mount_afs: description: An error occured while was mounting itself.
run_rpc failed: Somehow the main NFS server loop failed. This error ``should never happen''.
unable to free rpc arguments in amqprog_1: The incoming arguments to the AMQ server could not be free'ed.
unable to free rpc arguments in nfs_program_1: The incoming arguments to the NFS server could not be free'ed.
unable to register (AMQ_PROGRAM, AMQ_VERSION, udp): The AMQ server could not be registered with the local portmapper or the internal RPC dispatcher.
unable to register (NFS_PROGRAM, NFS_VERSION, 0): The NFS server could not be registered with the internal RPC dispatcher.

Info messages generates information messages to record state changes. These messages are selected by -x info on the command line. When syslog(3) is being used, they are logged with level LOG_INFO. The messages listed below can be generated and are in a format suitable for simple statistical analysis. ``mount-info'' is the string that is displayed by in its mount information column and placed in the system mount table.

mount of "path" on fs timed out: Attempts to mount a filesystem for the given automount point have failed to complete within 30 seconds.
"path" forcibly timed out: An automount point has been timed out by the command.
restarting mount-info on fs: A pre-mounted file system has been noted.
"path" has timed out: No access to the automount point has been made within the timeout period.
file server rhost is down - timeout of "path" ignored: An automount point has timed out, but the corresponding file server is known to be down. This message is only produced once for each mount point for which the server is down.
Re-synchronizing cache for map map: The named map has been modified and the internal cache is being re-synchronized.
Filehandle denied for "rhost:rfs": The mount daemon refused to return a file handle for the requested filesystem.
Filehandle error for "rhost:rfs": description: The mount daemon gave some other error for the requested filesystem.
file server rhost type nfs starts up: A new file server has been referenced and is known to be up.
file server rhost type nfs starts down: A new file server has been referenced and is known to be down.
file server rhost type nfs is up: An file server that was previously down is now up.
file server rhost type nfs is down: An file server that was previously up is now down.
Finishing with status exit-status: is about to exit with the given exit status.
mount-info mounted fstype type on fs: A new file system has been mounted.
mount-info restarted fstype type on fs: is using a pre-mounted filesystem to satisfy a mount request.
mount-info unmounted fstype type from fs: A file system has been unmounted.
mount-info unmounted fstype type from fs link fs/sublink: A file system of which only a sub-directory was in use has been unmounted.

Acknowledgements & Trademarks Thanks to the Formal Methods Group at Imperial College for suffering patiently while was being developed on their machines.

Thanks to the many people who have helped with the development of especially Piete Brooks at the Cambridge University Computing Lab for many hours of testing, experimentation and discussion.