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GNU Info (am-utils.info)Automount FilesystemAutomount Filesystem (`auto') ============================= The "auto" (`type:=auto') filesystem type creates a new automount point below an existing automount point. Top-level automount points appear as system mount points. An automount mount point can also appear as a sub-directory of an existing automount point. This allows some additional structure to be added, for example to mimic the mount tree of another machine. The following options may be specified: `cache' specifies whether the data in this mount-map should be cached. The default value is `none', in which case no caching is done in order to conserve memory. However, better performance and reliability can be obtained by caching some or all of a mount-map. If the cache option specifies `all', the entire map is enumerated when the mount point is created. If the cache option specifies `inc', caching is done incrementally as and when data is required. Some map types do not support cache mode `all', in which case `inc' is used whenever `all' is requested. Caching can be entirely disabled by using cache mode `none'. If the cache option specifies `regexp' then the entire map will be enumerated and each key will be treated as an egrep-style regular expression. The order in which a cached map is searched does not correspond to the ordering in the source map so the regular expressions should be mutually exclusive to avoid confusion. Each mount map type has a default cache type, usually `inc', which can be selected by specifying `mapdefault'. The cache mode for a mount map can only be selected on the command line. Starting Amd with the command: amd /homes hesiod.homes -cache:=inc will cause `/homes' to be automounted using the "Hesiod" name server with local incremental caching of all successfully resolved names. All cached data is forgotten whenever Amd receives a `SIGHUP' signal and, if cache `all' mode was selected, the cache will be reloaded. This can be used to inform Amd that a map has been updated. In addition, whenever a cache lookup fails and Amd needs to examine a map, the map's modify time is examined. If the cache is out of date with respect to the map then it is flushed as if a `SIGHUP' had been received. An additional option (`sync') may be specified to force Amd to check the map's modify time whenever a cached entry is being used. For example, an incremental, synchronized cache would be created by the following command: amd /homes hesiod.homes -cache:=inc,sync `fs' specifies the name of the mount map to use for the new mount point. Arguably this should have been specified with the `${rfs}' option but we are now stuck with it due to historical accident. `pref' alters the name that is looked up in the mount map. If `${pref}', the "prefix", is non-null then it is prepended to the name requested by the kernel "before" the map is searched. `opts' Normally, `auto' style maps are not browsable even if you turn on directory browsability (Note: browsable_dirs Parameter). To enable browsing entries in `auto' maps, specify `opts:=browsable' in the description of this map. The server `dylan.doc.ic.ac.uk' has two user disks: `/dev/dsk/2s0' and `/dev/dsk/5s0'. These are accessed as `/home/dylan/dk2' and `/home/dylan/dk5' respectively. Since `/home' is already an automount point, this naming is achieved with the following map entries: dylan type:=auto;fs:=${map};pref:=${key}/ dylan/dk2 type:=ufs;dev:=/dev/dsk/2s0 dylan/dk5 type:=ufs;dev:=/dev/dsk/5s0 automatically generated by info2www version 1.2.2.9 |