+++ /dev/null
-============
-Introduction
-============
-
-There are times when data needs to be excluded from a backup. When
-these times arise be confident that Amanda has this capability.
-(Actually it's not Amanda, it's tar.) There are three ways of
-excluding data in an Amanda backup:
-
- * Exclude an individual item explicitly in the dumptype
- * Utilize an Exclude List
- * Do not include the data in the disklist
-
-This document is based on Amanda 2.4.2 and some of this might not
-work with older versions. This was compiled from my personal
-experience and with help from the members of the amanda-users
-mailing list when I was originally setting this up, to whom I wish
-to thank for all of their support.
-
-============
-Please Read
-============
-
-As far as I am able to tell the only way to exclude files or
-directories with Amanda is to use gnutar as the dump program
-(others?). The file system dump programs provided with unix systems
-(e.g. dump, ufsdump) get data at a raw drive level and generally
-do not allow exclusion of specific files or directories.
-
-The GNU version of tar, (gnutar or gtar), reads its data at a
-file system, (or higher), level and does include the option to
-exclude specific files and/or directories. It should be mentioned
-here that tar will change the access times on files. Tar has the
-ability to preserve the access times however, doing so effectively
-disables incremental backups since resetting the access time alters
-the inode change time, which in turn causes the file to look like
-it needs to be archived again.
-
-The only exception that I am aware of is to just not include the
-data in question in the disklist. This option may not be suitable
-for everyone's needs and can confuse the issue some, so I have
-elected to include this mechanism in its own section named "Do not
-include the data in the disklist".
-
-For the purpose of this document an Amanda backup configuration
-named "exclude-test" will be used. The machine that contains the
-tape drive which receives data to be archived will be referred to
-as "SERVER". The machine that data is being archived from will be
-referred to as "CLIENT". These two systems are usually different
-machines but are not required to be, and may be the same machine.
-Parts of this setup are on the server and some are on the client.
-
-***************
-** IMPORTANT **
-***************
-
-When Amanda attempts to exclude a file or directory it does so
-relative to the area being archived. For example if "/var" is in
-your disklist and want to exclude "/var/log/somefile", then your
-exclude file would contain "./log/somefile". You may use one
-exclude file in multiple dump types without any restriction.
-
-===============
-Before We Begin
-===============
-
-The first step that should be taken is to verify that backups are
-currently working. Connect to SERVER and run amcheck as your Amanda
-user, to verify that there are no errors in the current setup.
-
- $ amcheck -cl CLIENT
-
-Output should look something like below for success:
-
- Amanda Tape Server Host Check
- -----------------------------
-
- /path/to/holding-disk: 4771300 KB disk space available, that's plenty.
- Amanda Backup Client Hosts Check
- --------------------------------
- Client check: 1 host checked in 0.084 seconds, 0 problems found.
-
-Next make sure that gnutar is the dump program currently in use.
-The easiest way to tell if your dumptype is using gnutar is to run
-the following:
-
- $ amadmin exclude-test disklist CLIENT
-
-Among all the output is the "program" value currently in use. This
-value is also specified with the "program" option in the dumptype.
-If the dumptype has the line "program GNUTAR" your setup should ready
-to exclude data.
-
-If gnutar is not in use add the line "program GNUTAR" to the
-dumptype, and then run amcheck again to verify that backups should
-work. The capitalization of GNUTAR is required in the current
-version of amanda.
-
-The dumptype should look something like:
-
-define dumptype exclude-test {
- comment "test dumptype for documentation"
- priority high
- program "GNUTAR"
-}
-
-=============================
-Choosing an exclude mechanism
-=============================
-
-If the need is to exclude only one file or directory then the
-easiest way to accomplish this is to exclude an individual item
-explicitly in the dumptype. If the need is to exclude multiple
-files or directories then use an Exclude List.
-
-==================
-Exclude Mechanisms
-==================
-
-** Exclude an individual item explicitly in the dumptype **
-
-The easiest way to exclude a file or directory is to specify it
-with the "exclude" option in the dumptype. This option accepts an
-argument of the file or directory to be excluded. Amanda allows
-only one exclude option in any dumptype at a time. Any path
-specified to be excluded must be encapsulated with quotes. Continuing
-with our example from above "/var/log/somefile" and using the same
-dumptype as above, the dumptype would now look like:
-
-define dumptype exclude-test {
- comment "test dumptype for documentation"
- priority high
- program "GNUTAR"
- exclude "./log/somefile"
-}
-
-Next run amcheck again to verify that there are no problems with
-the revised Amanda configuration. If the data is not being excluded
-as expected please see the Troubleshooting section below. This
-completes the setup of excluding an individual item in the dumptype.
-
-
-** Utilize an Exclude List **
-
-An exclude list is a file that resides on the CLIENT machine and
-contains paths to be excluded, one per line. This file can be in
-any location on the CLIENT so long as the same path is specified
-in the dumptype. Some find /usr/local/etc/amanda an appropriate
-location, but it is up to you. I personally like to have a
-subdirectory for exclude files but it is up to you where you place
-this file.
-
-The exclude file may also be placed in the area being archived.
-This is an easy way to have a different exclusion file for each
-disklist entry without needing separate dumptype definitions. To
-use this technique, enter a path relative to the area being archived
-as the exclude file below instead of an absolute path.
-
-Connect to CLIENT and create the exclude directory as root. For
-example:
-
- $ mkdir -p /usr/local/etc/amanda/exclude
- $ cd /usr/local/etc/amanda/exclude
-
-Next create the exclude list for Amanda to use. You can name the
-exclude file anything you wish it to be. Create a file, and in
-this file place all paths to files and directories that are to be
-excluded. Keeping with the /var example, assume that
-/var/log/XFree86.0.log, and /var/log/maillog need to be excluded.
-Remember that all paths are relative. The exclude list would look
-like:
-
- ./log/XFree86.0.log
- ./log/maillog
-
-Make sure that permissions are restricted on this file. Run the
-following as root, where exclude-filename is the name of the file
-you just created. For example:
-
- $ chmod 644 /usr/local/etc/amanda/exclude/exclude-filename
-
-This concludes the necessary configuration on the client.
-
-Connect to SERVER and cd to the exclude-test Amanda configuration
-directory. Edit the Amanda configuration file e.g. amanda.conf.
-Add an entry similar to the following line, to the dumptype for
-the client in question, where the exclude-filename is the file that
-was created on CLIENT in the step above including the quotes.
-For example:
-
- exclude list "/usr/local/etc/amanda/exclude/exclude-filename"
-
-The new dumptype should look something like:
-
- define dumptype exclude-test{
- comment "test dumptype for documentation"
- priority high
- program "GNUTAR"
- exclude list "/usr/local/etc/amanda/exclude/exclude-filename"
- }
-
-Save the file. Run amcheck again to verify that there are no problems
-with the revised Amanda configuration. If amcheck succeeds then
-run amdump to verify the data is being excluded correctly. If the
-data is not being excluded as expected please see the Troubleshooting
-section below. This completes the setup of an exclude list.
-
-** Do not include the data in the disklist **
-
-Amanda uses disklist entries to define which directories or partitions
-should be archived. This allows us to exclude data by just not
-placing the data in question in the disklist. Assume that there
-is a disk mounted on /example. The directory /example has five
-subdirectories "a", "b", "c", "d", and "e". The directories "a",
-"b", and "c" need to be archived, while "d" and "e" should not.
-This can be accomplished by not specifying "d" and "e" in the
-disklist. Using the same dumptype and host in the above examples
-the disklist would contain:
-
- CLIENT /examples/a exclude-test
- CLIENT /examples/b exclude-test
- CLIENT /examples/c exclude-test
-
-Run amcheck to verify that Amanda is working correctly. If the
-data is not being excluded as expected please see the Troubleshooting
-section below. This completes the setup of using a disklist to
-exclude data.
-
-=========
-Expresion
-=========
-
-Quiz: what is the difference between the following entries in
-an exclude list?
-
-1 ./foo
-2 ./foo/
-3 ./foo/*
-
-case 1 directory ./foo won't be in the backup image (that's what you want)
-case 2 matches nothing (don't use it)
-case 3 directory ./foo will be in the backup image but nothing below it.
-
-==================
-Wildcard Expansion
-==================
-
-Amanda has the ability to use wildcard expansion while excluding
-data as implemented by tar(1). The only places that wildcard
-expansion is allowed is in the "exclude" option in the dumptype,
-or in the exclude list. Some simple examples:
-
-Exclude any file or directory that ends in ".log" e.g. ppp.log,
-XFree86.0.log
-
- ./*.log
-
-Exclude any file or directory with the string "log" e.g. logfile,
-maillog, syslog, ppp.log, XFree86.0.log
-
- */*log*
-
-Exclude any file or directory that starts with string "cron" and ends in
-".gz" e.g. cron.1.gz, cron.2.gz, log/cron.1.gz
-
- ./*cron*.gz
-
-The question mark can be used to specify a single character. e.g.
-log.1, log.2, etc
-
- ./log.?
-
-===============
-Troubleshooting
-===============
-
-1. If you find that you are having trouble getting the exclude
-patterns to match correctly, check out this really cool script
-written by John R. Jackson.
-
- ftp://gandalf.cc.purdue.edu/pub/amanda/gtartest-exclude
-
-This script allows you to test your patterns before placing them
-in an exclude list or in the dumptype. Instructions on how to run
-the script are included in the script.
-
-2. Broken gnutar? There are versions of gnutar that do not correctly
-exclude data. Version 1.12 (plus the Amanda patches from
-www.amanda.org) are known to work correctly, as does version 1.13.19
-(and later). Anything else is questionable.
-
-3. The ps command is your friend. Connect to CLIENT and run a "ps
-ax | grep tar", (ps -ef | grep tar) on Solaris, to see exactly how
-the tar command is running. Look in the output for the --exclude
-or --exclude-from options in the running tar process. For example:
-
- $ ps ax | grep tar
- 11078 ? R 0:37 /bin/tar --create --directory /var
- --listed-incremental /var/lib/amanda/gnutar-lists/CLIENTvar_0.new
- --sparse --one-file-system --ignore-failed-read --totals --file
- /dev/null --exclude-from=/usr/local/etc/amanda/exclude-test/exclude.var
- .
-
-In the above output notice the string "--exclude-from=". The string
-following the "=" is the exclude file currently in use. If the
-string was "--exclude" then the string following the "=" is the
-file or directory that is currently set to be excluded.
-
-4. Check out the book "Unix Backup & Recovery", written by W. Cutris
-Preston. It contains a chapter on Amanda written by John R. Jackson.
-It can be read online at www.amanda.org.
-
-5. Contact the amanda-users mailing list. Subscription information
-is available at www.amanda.org.
-
-
-Written by Andrew Hall <ahall@secureworks.net> August 6, 2001.
projects / debian / amanda / blobdiff