From: Richard W.M. Jones Date: Thu, 27 Nov 2014 10:42:10 +0000 (+0000) Subject: Add section "Notes on disk format" to the manual. X-Git-Url: http://git.annexia.org/?a=commitdiff_plain;ds=inline;p=virt-bmap.git Add section "Notes on disk format" to the manual. --- diff --git a/virt-bmap.pod b/virt-bmap.pod index 14f56ac..9e66147 100644 --- a/virt-bmap.pod +++ b/virt-bmap.pod @@ -85,6 +85,19 @@ file The following column(s) identify the file or object. +=head2 Notes on disk format + +The virt-bmap tool does I auto-detect the disk format: you have +to specify the correct format. + +Although in theory you can use any disk format, we found that block +map detection works much more reliably if the disk is in C +format. With other formats it appears that structures within the +format (like the qcow2 header) can confuse disk format detection, +resulting in files appearing to be read which are probably not being +accessed. Therefore it is recommended that you first convert disks to +raw using a tool such as L. + =head2 bmaplogger: nbdkit plugin to observe file accesses The second tool is an L plugin called C. Use @@ -104,8 +117,7 @@ observe the files accessed by a virtual machine when booting: Set the format of the input disk image. The default is C. -Note this is I auto-detected, you I specify the -correct format. +See L above. =item B<--help> @@ -159,6 +171,7 @@ Send the log output to a file. L, L, L, +L, L, L