[cups.bugs] CUPS and Shorewall firewall interfering with each

Erik Slagter eslagter at wlz.nl
Mon Jan 3 01:29:47 PST 2005

On Thu, 2004-12-30 at 09:56 -0500, Erik Reuter wrote:
> CUPS was working fine to print to my Epson C84 (network connected via a
> Netgear PS101 print server using lpd://PS101.IP.address/raw ) until I
> installed the Shorewall firewall on the machine running CUPS.
> When I installed Shorewall, I opened up port 515 for lpd printing from
> the firewall to the local network
>    ACCEPT          fw              loc             tcp     515  # LPD
> so I didn't anticipate any problems with CUPS printing.
> However, as soon as I started the Shorewall firewall, I found that I
> could no longer print from the firewall machine using CUPS.

IMHO this is not a BUG.

Please note that cups uses

a) various ports (like http (80/tcp) and ipp (631/tcp and 631/udp).
b) broadcast packets (on 631/udp)

These must be opened as well.

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