escher(1M) escher(1M)NAME escher - autorecovery administration SYNOPSIS escher [-y] [-m] escher file... DESCRIPTION escher determines if the regular files in the autorecovery file systems (see autorecovery(8)) are out of date with respect to the root or usr file systems. If a file is determined to be out of date, a message will appear asking if the new file should be copied to the autorecovery file system. escher will optionally mail to root a list of out of date files, copy newer files to the autorecovery file systems or, if given a list of filenames, will add these files to the Configuration Master List (CML) and copy these files to the autorecovery file systems. The CML is described in cml(4). Note: escher may be run only by the superuser. A hard disk may be divided into partitions. Each partition contains one file system (see fs(4)). Information on all the partitions on a disk is kept in the disk partition map (see dpme(4)) for that disk. One of the fields in a dpme is the cluster number. This is used to identify the group of partitions escher should use. escher will only recognize partitions which reside on one disk. escher will read the cluster number from nvram, (see nvram(7)) and locate all the partitions in that cluster. A cluster must contain a root partition, a swap partition, and at least one autorecovery partition. A cluster may also contain a partition known as the usr partition. The usr partition contains a file system that is intended to be mounted on /usr. There may be multiple autorecovery parti- tions in a cluster. An autorecovery file system contains copies of regular files that are needed for a minimal multiuser A/UX system. There are no special files in autorecovery file systems. The CML is a list of files required for multiuser A/UX and resides on the root file system. escher will check each file that is listed in the CML; escher ignores all special files and directories. If any of these files are invalid or are newer than the corresponding file in the autorecovery file sys- tems, the user will be asked if the file should be copied to the autorecovery file systems. April, 1990 1
escher(1M) escher(1M)For each file that is copied, a new CML entry will be made. A CML entry contains a list of ``rules'' about the file that specify what the file's attributes should be. There are CML rules for the following file attributes: file type linked filename size modification time ownership permissions major and minor device numbers version checksum The CML entry that is created by escher will have different values from the previous entry and will have a limited number of attribute specifications. This entry will have rules for: filename file type size modification time ownership permissions escher flag options are: -m Mail to root a list of files in autorecovery file sys- tems that are no longer faithful copies and may need to be updated. With this option alone, no files will be copied to autorecovery file systems. -y Assume a ``yes'' response to questions that would be asked about copying files to autorecovery file systems. It is advisable to first run escher with -m and verify that all of the listed files are ``good'' before using this option. It is possible that a file could be cor- rupt and should not be copied to the autorecovery file systems. escher with both -y and -m will update all the files in au- torecovery file systems that are necessary and mail a list of changed files to root. The -y and -m flag options may not be used when a list of files is present on the command line. When escher is given a list of filenames, it will create an entry in the CML list for each file and copy it to the au- torecovery file systems. The filenames must be full path- names, beginning with /. The CML entry will have simple 2 April, 1990
escher(1M) escher(1M)rules as described above. The named files should be files that are not currently in the CML and do not reside in au- torecovery file systems. FILES /etc/escher /etc/eschatology/init2files SEE ALSO cml(4), dpme(4), fs(4), nvram(7), autorecovery(8). DIAGNOSTICS The diagnostic messages are intended to be self-explanatory. If an autorecovery file system runs out of space while esch- er is copying new files to it, escher will not attempt to update any of the other files contained in that file system. escher will display a message that indicates the file system is full. WARNINGS When escher is given a list of files to be added to the CML, the user must include the directories the files reside in. In order for a file to be restored through autorecovery, all the directories in the pathname of a file must also be in the CML list. escher requires that the CML file be sorted by filename. April, 1990 3