NetBackup 5.1 MP4 on linux kernel 2.6

I have a 3 TB filesystem on a NetApp that I'm backing up via NDMP.  The 
filesystem consists of about 56 million files and growing.  I can 
duplicate a weekly cumulative of this just fine, which consists of about 
22 million files, but duplicating the Full backup always fails, both 
manually and when Vault tries.  Is 56M above some magic threshold that I 
can adjust?  Is this a simple timeout that can be adjusted?  In the vault 
log it says:
"Unable to create data socket to receive TIR data"
But TIR isn't even an option in the NDMP backup type.

Please help

Here are the gory details:

$ sudo bpimmedia -policy NDMP_ftp -L
netapp01_1177753767  NDMP_ftp   FULL  5   55338467 N  N  R  1   04:49 
07/30/2007
  1 IDX 14684123 RMed hcart2  2         0         backup1.dm 0 
200030
-snip-
netapp01_1177150165  NDMP_ftp   CINC  3   21787569 N  N  R  1   05:09 
05/12/2007
  1 IDX  8525374 RMed hcart2  2         0         backup1.dm 0 
200326

And from the Vault log:
01:00:00 INF - Duplicating policy NDMP_ftp schedule Full backup id 
netapp01_1177753767 copy 1 created on 04/28/2007 04:49:27 on source media 
id 200536
01:00:01 INF - Waiting for positioning of media id 200301 on server 
backup1 for writing.
01:00:01 INF - Waiting for positioning of media id 200536 on server 
backup1 for reading.
01:00:02 INF - Beginning duplicate on server backup1 of client netapp01.
01:00:03 INF - Beginning duplication on server backup1 of client netapp01,
creating copy 2 on destination media id 200301
01:01:24 ERR - Unable to create data socket to receive TIR data.
01:01:36 INF - host backup1 backup id netapp01_1177753767 read failed,
socket write failed (24).

01:01:36 INF - host backup1 backupid netapp01_1177753767 write failed,
timed out connecting to client (54).

01:01:36 INF - Duplicate of backup id netapp01_1177753767 failed, timed 
out connecting to client (54).

TIA
-- 
Joe Royer / SysAdmin / Digital Motorworks / 512-692-1028


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