doc: Edits to the 'afsd -volume-ttl' manpage

[openafs.git] / doc / man-pages / pod8 / afsd.pod

diff --git a/doc/man-pages/pod8/afsd.pod b/doc/man-pages/pod8/afsd.pod
index dd48a16..65a27a6 100644 (file)
--- a/doc/man-pages/pod8/afsd.pod
+++ b/doc/man-pages/pod8/afsd.pod
@@ -34,6 +34,7 @@ B<afsd> [B<-afsdb>] [B<-backuptree>]
      [B<-disable-dynamic-vcaches>] 
      S<<< [B<-volumes> <I<number of volume entries>>] >>>
      [B<-waitclose>] [B<-rxmaxfrags> <I<max # of fragments>>]
+     S<<< [B<-volume-ttl> <I<vldb cache timeout>>] >>>
 
 =for html
 </div>
@@ -753,6 +754,28 @@ affected in previous versions of the Cache Manager, to perform synchronous
 writes to the File Server, is now the default behavior. To perform
 asynchronous writes in certain cases, use the B<fs storebehind> command.
 
+=item B<-volume-ttl>
+
+Specifies the maximum amount of time the Cache Manager will cache volume
+information retrieved from VL Servers.
+
+By default, the Cache Manager will cache read-only volume information as long
+as a volume callback is held for that volume. The callback may be held as long
+as files in the read-only volume are being accessed, with no upper limit. For
+read/write volumes, by default the Cache Manager will cache volume information
+forever, until a fileserver returns a volume-level error in response to
+accessing files in that volume.
+
+Use the B<-volume-ttl> option to specify the maximum amount of time in seconds
+that volume information will be cached, regardless of connectivity to the
+fileservers. Lowering this value can make the Cache Manager recover more
+quickly from certain volume/fileserver errors, but will increase the load on
+the VL Servers for contacted cells.
+
+A typical value is 7200 seconds (2 hours), which is the same as the default
+callback duration for read-only volumes. The minimum valid value is 600 seconds
+(10 minutes).
+
 =back
 
 =head1 EXAMPLES