>> What I would like to do is use one >> normally, and mount the second system read-only to perform backups and >> to rsync the filesystem to another filesystem. When it's mounted >> read-write from another system, will mounting the same filesystem >> read-only cause the journal to be committed at the time it's mounted? > >Yes, that is very bad. Can you elaborate why mounting a filesystem read-only is "dangerous"? > >> If so, is that a bad thing, that is, will it corrupt the filesystem? > >Yes, it can corrupt the filesystem. I assume, then, that mounting the filesystem read-only flushes the journal. Why does flushing it "early" corrupt the filesystem? > >> Are journal events handled similar to databases, with regard to transaction >> processing of journal events, or could playing "partial" journal events >> (if there is such a thing) cause corruption? Is mounting the read-only >> instance as a ext2 filesystem the best solution, or does it matter if >> it's mounted ext2 or ext3 as long as it's read-only? > >You can't mount it as ext2. > Why? It seemed to work, although I'm not sure, from the comments I've been getting, that it's safe. The ext3-faq says: How do I convert my ext3 partition back to ext2? Actually there is only little need to do so, because in most cases it is sufficient to mount the partition explicitely as ext2. >I would instead use a block-device level backup, like "dump" if you really >need to do it this way. You are probably better off just doing the backup >from the primary node. > >Cheers, Andreas >-- >Andreas Dilger >Principal Software Engineer >Cluster File Systems, Inc. > -- Jeff Garlough __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ Ext3-users mailing list Ext3-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/ext3-users
