Denish Patel <denish@xxxxxxxxxx> wrote: > Craig James <cjames@xxxxxxxxxxxxxx> wrote: >> Jeff Frost <jeff@xxxxxxxxxxxxx> wrote: >>>> Craig James <cjames@xxxxxxxxxxxxxx> wrote: >>>> >>>> After I rsync the postgres data directory, do I need the WAL >>>> files from the source (they're on a separate disk, not part of >>>> the postgres data directory)? Can/should I erase the WAL >>>> directory of the destination? >>> >>> Yes, you need the WAL files. >> >> Now I have two directly conflicting answers. You say the WAL >> files are needed even though the DB is shut off, and Payal Singh >> says I don't need the WAL files (but I don't think he cc'd the >> mailing list). >> >> Why are the WAL files necessary if the DB is shut off? Why >> can't they just be erased? >> >> It's a gigabyte of copying that I was hoping to avoid. > Payal is right. You don't need WAL for Cold backup. This experiment took far less time than reading the thread: kgrittn@Kevin-Desktop:~/pg/master$ pg_ctl -D Debug/data -m fast -w stop waiting for server to shut down.... done server stopped kgrittn@Kevin-Desktop:~/pg/master$ mkdir Debug/data/xlog2 kgrittn@Kevin-Desktop:~/pg/master$ mv Debug/data/pg_xlog/* Debug/data/xlog2/ kgrittn@Kevin-Desktop:~/pg/master$ rm -f Debug/data/logfile ; pg_ctl -D Debug/data -l Debug/data/logfile -w start || cat Debug/data/logfile waiting for server to start........ stopped waiting pg_ctl: could not start server Examine the log output. LOG: database system was shut down at 2013-12-06 15:31:27 CST LOG: creating missing WAL directory "pg_xlog/archive_status" LOG: invalid primary checkpoint record LOG: invalid secondary checkpoint record PANIC: could not locate a valid checkpoint record LOG: startup process (PID 15471) was terminated by signal 6: Aborted LOG: aborting startup due to startup process failure Now, if you're very clever you might be able to copy just *selected* WAL files. You've gotta ask yourself a question: "Do I feel lucky?" Well, do ya? -- Kevin Grittner EDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
