Re: [libvirt] question about syntax of storage volume <target> element

On 9/28/18 12:54 AM, Jim Fehlig wrote: The [1] pool/vol page is meant to be a bit more "generic" with respect to the general format of the <target>...<path>... field because some fields can have different formats/expectations. The [0] storage page should represent more details for each storage backend's expectations over the format to be used. Although my recollection is that it's modified/patched far less frequently than the [1] page. When in doubt though, I usually search "tests/*/*.{xml|args} and then of course looking at the source code. If I must, I'll look at the RNG files. In this case storagevol.rng says @path could be "anyURI" or "absFilePath", nothing specific for RBD. My git history search shows [0] seems to have been originally written and intended as is seen now (commit 74951eade). In the long run it doesn't matter if the <path> has the "rbd:" prefix because virStorageSourceParseRBDColonString will strip it before duplicating and then later qemuBuildNetworkDriveStr will slap it back onto the command line. How's that for a round-about way of saying - it doesn't seem to matter. I don't think "rbd:rbd/" is the prefix, just the "rbd:". It just so happens the example shows the RBD pool "source" name as "rbd" and the "volume" as "myvol". If you look at the <key> that's more indicative of path to the volume. The example when paired with the pool of source name "rbdpool" probably should have shown "rbd:rbdpool/myvol" and the key "rbdpool/myvol" (to be less confusing). As for "expected" format - well being consistent would be "nice" - probably depends on when the code was originally added though. Adding new or consistent formats ends up being a coding and documenting exercise and we never seem to be able to "lose" old formats and aren't supposed to "rewrite" someone's files - so we're stuck. John