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Diffstat (limited to 'contrib/pg_resetxlog/README.pg_resetxlog')
-rw-r--r-- | contrib/pg_resetxlog/README.pg_resetxlog | 42 |
1 files changed, 0 insertions, 42 deletions
diff --git a/contrib/pg_resetxlog/README.pg_resetxlog b/contrib/pg_resetxlog/README.pg_resetxlog deleted file mode 100644 index 9802cdddd32..00000000000 --- a/contrib/pg_resetxlog/README.pg_resetxlog +++ /dev/null @@ -1,42 +0,0 @@ -pg_resetxlog is a program to clear the WAL transaction log (stored in -$PGDATA/pg_xlog/), replacing whatever had been in it with just a dummy -shutdown-checkpoint record. It also regenerates the pg_control file -if necessary. - -THIS PROGRAM WILL DESTROY VALUABLE LOG DATA!!! Don't run it unless you -really need it!!! - -pg_resetxlog is primarily intended for disaster recovery --- that is, -if your pg_control and/or xlog are hosed badly enough that Postgres refuses -to start up, this program will get you past that problem and let you get to -your data files. But realize that without the xlog, your data files may be -corrupt due to partially-applied transactions, incomplete index-file -updates, etc. You should dump your data, check it for accuracy, then initdb -and reload. - -A secondary purpose is to cope with xlog format changes without requiring -initdb. To use pg_resetxlog for this purpose, just be sure that you have -cleanly shut down your old postmaster (if you're not sure, see the contrib -module pg_controldata and run it to be sure the DB state is SHUTDOWN). -Then run pg_resetxlog, and finally install and start the new version of -the database software. - -A tertiary purpose is its use by pg_upgrade to set the next transaction -id and checkpoint location in pg_control. - -To run the program, make sure your postmaster is not running, then -(as the Postgres admin user) do - - pg_resetxlog $PGDATA - -As a safety measure, the target data directory must be specified on the -command line, it cannot be defaulted. - -If pg_resetxlog complains that it can't reconstruct valid data for pg_control, -you can force it to invent plausible data values with - - pg_resetxlog -f $PGDATA - -If this turns out to be necessary then you *definitely* should plan on -immediate dump, initdb, reload --- any modifications you do to the database -after "pg_resetxlog -f" would be likely to corrupt things even worse. |