commit e7d1bd38b1d1de6b1bec603eeff915ebb57f3c37

Author: zoulasc <christos@zoulas.com>

Date:   Thu Mar 10 17:50:34 2016 -0500

    - There is really no ti-rpc nfsv4, so don't send one; instead send a v3 for now.

diff --git a/amd/srvr_nfs.c b/amd/srvr_nfs.c

index b7c852c..1418a1a 100644

--- a/amd/srvr_nfs.c

+++ b/amd/srvr_nfs.c

@@ -140,6 +140,7 @@ create_ping_payload(u_long nfs_version)

 {

   XDR ping_xdr;

   struct rpc_msg ping_msg;

+  int rpc_version;

   /*

    * Non nfs mounts like /afs/glue.umd.edu have ended up here.

@@ -150,7 +151,17 @@ create_ping_payload(u_long nfs_version)

   } else

     plog(XLOG_INFO, "%s: nfs_version: %d", __func__, (int) nfs_version);

-  rpc_msg_init(&ping_msg, NFS_PROGRAM, nfs_version, NFSPROC_NULL);

+  /*

+   * There is really no ti-rpc version for NFSv4; most servers respond

+   * with "program unavailable", which is ok since we don't check the

+   * payload, we just care about the pings. Some servers though are

+   * antisocial (Isilon) and don't respond (which is their right to do).

+   * Eventually we should make a new mechanism to do server pings for

+   * NFSv4, but for now it is easiest to downgrade the RPC version to 3.

+   */

+  rpc_version = nfs_version == 4 ? 3 : nfs_version;

+

+  rpc_msg_init(&ping_msg, NFS_PROGRAM, rpc_version, NFSPROC_NULL);

   /*

    * Create an XDR endpoint

@@ -600,6 +611,7 @@ nfs_keepalive(voidp v)

   case ENETUNREACH:

   case EHOSTDOWN:

   case EHOSTUNREACH:

+    dlog("Failed to NFS ping to %s (%d)", fs->fs_host, error);

     np->np_ping = MAX_ALLOWED_PINGS;	/* immediately down */

     np->np_ttl = (time_t) 0;

     /*