Add new function dumpconfig: dump the configuration information

directly off the drives.

This command shows a minor problem: it requires that the device nodes
exist, whereas kernel Vinum does not.  Thus dumpconfig may show no
configuration for certain drives which are up and happily running.
This is documented in the man page.

1 files changed, 18 insertions, 0 deletions

diff --git a/sbin/vinum/vinum.8 b/sbin/vinum/vinum.8
index fce1a43..068299e 100644
--- a/sbin/vinum/vinum.8
+++ b/sbin/vinum/vinum.8
@@ -89,6 +89,12 @@ Set debugging flags.
 .in +1i
 Detach a plex or subdisk from the volume or plex to which it is attached.
 .in
+.Cd dumpconfig
+.Op Ar drive ...
+.in +1i
+List the configuration information stored on the specified drives, or all drives
+in the system if no drive names are specified.
+.in
 .Cd info
 .Op Fl v
 .Op Fl V
@@ -627,6 +633,18 @@ does not reduce the number of subdisks in a striped or RAID-5 plex.  Instead,
 the subdisk is marked absent, and can later be replaced with the
 .Nm attach
 command.
+.It Nm dumpconfig  Op Ar drive ...
+.Pp
+.Nm
+.Ar dumpconfig
+shows the configuration information stored on the specified drives.  If no drive
+names are specified,
+.Nm dumpconfig
+searches all drives on the system for Vinum partitions and dumps the
+information.  If configuration updates are disabled, it is possible that this
+information is not the same as the information returned by the
+.Nm list
+command.  This command is used primarily for maintenance and debugging.
 .It Nm info
 .br
 .Nm