[Samba] Unable to print, many rpcd_spoolss processes running

[Paul Griffith]

Hello,

I ran into a printing issue (users not able to print) with Samba 4.16.6. Not sure if this a one-off problem.  Posting it just in case it helps someone in the future.

In log.smb I was seeing the following error:

rpc_pipe_open_interface: Could not connect to spoolss pipe: NT_STATUS_IO_TIMEOUT
[2022/11/09 00:00:25.530143,  0, pid=2888076, effective(24767, 3000), real(24767, 0)] ../../source3/rpc_server/rpc_ncacn_np.c:209(rpc_pipe_open_interface)
  rpc_pipe_open_interface: Could not connect to spoolss pipe: NT_STATUS_IO_TIMEOUT
[2022/11/09 00:00:30.418012,  1, pid=2904322, effective(0, 0), real(0, 0)] ../../source3/smbd/service.c:357(create_connection_session_info)

In log.rpcd_spoolss I see the following errors filling the log file:
--
[2022/11/08 17:52:53,  1] ../../source3/rpc_server/rpcd_spoolss.c:68(spoolss_servers)
  spoolss_servers: printing_subsystem_init() failed
[2022/11/08 17:53:03,  0] ../../source3/rpc_server/rpc_worker.c:1107(rpc_worker_main)

As it turns out, we had 494 rpcd_spoolss processes running. 

ps -ef | grep -i rpcd_spoolss
root     2878210 2877329  0 Nov08 ?        00:00:00 /xsys/pkg/samba-4.16.6/libexec/samba/rpcd_spoolss --configfile=/etc/samba/smb.conf --worker-group=7 --worker-index=0 --debuglevel=1
root     2878222 2877329  0 Nov08 ?        00:00:00 /xsys/pkg/samba-4.16.6/libexec/samba/rpcd_spoolss --configfile=/etc/samba/smb.conf --worker-group=7 --worker-index=1 --debuglevel=1
root     2878226 2877329  0 Nov08 ?        00:00:00 /xsys/pkg/samba-4.16.6/libexec/samba/rpcd_spoolss --configfile=/etc/samba/smb.conf --worker-group=7 --worker-index=2 --debuglevel=1
root     2878231 2877329  0 Nov08 ?        00:00:00 /xsys/pkg/samba-4.16.6/libexec/samba/rpcd_spoolss --configfile=/etc/samba/smb.conf --worker-group=7 --worker-index=3 --debuglevel=1
root     2878242 2877329  0 Nov08 ?        00:00:00 /xsys/pkg/samba-4.16.6/libexec/samba/rpcd_spoolss --configfile=/etc/samba/smb.conf --worker-group=7 --worker-index=4 --debuglevel=1
...snip...
root     2885076 2877329  0 Nov08 ?        00:00:00 /xsys/pkg/samba-4.16.6/libexec/samba/rpcd_spoolss --configfile=/etc/samba/smb.conf --worker-group=7 --worker-index=494 --debuglevel=1

Once I killed those processes our users were able to print, and there is only one process running.

Not sure why it was running so many rpcd_spoolss processes, could it be linked to a run-away print job, continuously trying to print?

create_connection_session_info: guest user (from session setup) not permitted to access this share (prt2)
[2022/11/09 00:00:20.402097,  1, pid=2904322, effective(0, 0), real(0, 0)] ../../source3/smbd/service.c:546(make_connection_snum)
  create_connection_session_info failed: NT_STATUS_ACCESS_DENIED
[2022/11/09 00:00:24.353782,  0, pid=2871591, effective(17848, 1000), real(17848, 0)] ../../source3/rpc_server/rpc_ncacn_np.c:209(rpc_pipe_open_interface)
  rpc_pipe_open_interface: Could not connect to spoolss pipe: NT_STATUS_IO_TIMEOUT
[2022/11/09 00:00:25.530143,  0, pid=2888076, effective(24767, 3000), real(24767, 0)] ../../source3/rpc_server/rpc_ncacn_np.c:209(rpc_pipe_open_interface)

We are running Rocky Linux 8.6 with self-compiled Samba 4.16.6

Thanks,
Paul