Some tunnels work. not others - why??

I am having an interesting ssh problem. I am hoping someone more knowledgeable than I can spot where I'm messing up.

I have Oracle databases on two different machines. I want to transfer the data (Oracle export/import) via piping to an ssh tunnel. I have done this successfully using ssh v1 (search on my address and it will come up, I posted the technique). Now I have to get this working with ssh v2 as that is our SA's dictate. Both machines are running Solaris 8; both Oracle databases are the same major and minor release.

I have established pubkey authentication and can log on directly between the two machines. I can do a simple transfer as follows:

$ ls -l |ssh username_at_targethost 'cat > list.txt'

Now I am trying to set up the Oracle export/import:
########################

On target machine:

mknod /tmp/inpipe p
imp xxx/xxx file=/tmp/inpipe &
########################

On source machine:

mknod /tmp/outpipe p
ssh username_at_targethost '/usr/local/bin/cat > /tmp/inpipe.dmp' < /tmp/outpipe.dmp &
exp xxx/xxx file=/tmp/outpipe.dmp
#########################

(I am using the full path to cat as I need the GNU version, this is Solaris 8 with the broken 'cat') I see the export start, but it acts as if it never gets tunneled to /tmp/inpipe.dmp on the target machine.  Under ssh v1 I could see the export and import working; here the export is working but I never see the import side go. Outpipe.dmp has data in it (i.e., size > 0), but inpipe.dmp does not (i.e., size stays at zero). Is there something special about using this technique with ssh v2 that I am missing from the man page?

TIA - Kind regards,
jh Received on Tue Feb 24 2004 - 14:09:57 CST