samba - May 2003 - Samba and printing=cups; printers disappear after a while

Hello there,

    We're using a reasonably large network of linux boxes, about 6 of
them offering printing services through CUPS. This has worked remarkably
stably for the last months, but we've got one lasting problem with Samba
that someone may have a hint to offer.

We use an smbd on one of the linux boxes that offers the shared CUPS
printers to the windows clients on the network. Now this smbd has the
following setup for the printing part:

    [global]
    # ... 
    printcap name = cups
    printer admin = @lpadmin, @users
    printing = cups
    #

    [printers]
    comment = All Printers
    path = /tmp
    create mask = 0700
    guest ok = Yes
    public = Yes
    printable = Yes
    print command = lpr -r -P %p -o raw %s
    lpq command = lpq -P %p
    lprm command = lprm -P %p

If we list out the printers on the box, we have something like:

    kiko@samba:~$ smbclient -L samba
    [...]
    Domain=[CONSAVE] OS=[Unix] Server=[Samba 2.2.3a-12.3 for Debian]
    [...]
        HP_1200_VENDA  Printer   HP Laserjet 1200
        MICRO03_PRINT  Printer   Epson LQ570+
        MICRO04_PRINT  Printer   Deskjet 600C
        MICRO05_PRINT  Printer   Epson LX-810L
        MICRO15_PRINT  Printer   HP840

        Server               Comment
        ---------            -------
        MICRO07              
        SAMBA                samba server (Samba 2.2.3a-12.3 for Debian)
        SERVWIN              

        Workgroup            Master
        ---------            -------
        CONSAVE              SAMBA

It is the PDC on the network, and the machines (windows 98 and windows
2000 server) connect to it normally. However, after a while, the
printers disappear from the listing there. When I query, it all looks
okay - except for the printers, which are gone. The period is in the
range of `days' but I can get a more precise measurement if it helps.

The machines that serve the printers are shut down every night. The smbd
server stays on continuously. Restarting smbd fixes this problem -- the
printers reappear. Printing through cups always works fine, even when
samba doesn't list the printers (only the Windows boxes are affected).

The logfiles are pretty huge, so I'm not sure what to look for.  Could
it be that other servers on the network are to blame? Has anyone ran
into this problem before, or has a hint as to how to debug it? 

Thanks for any help provided. Take care,
--
Christian Reis, Senior Engineer, Async Open Source, Brazil.
http://async.com.br/~kiko/ | [+55 16] 261 2331 | NMFL