HP LaserJet

[Eric Shubert]

Joseph Sinclair wrote:
> Trent Shipley wrote:
>> Eric Shubert wrote:
>>> Trent Shipley wrote:
>>>> GK wrote:
>>>>> Hey.
>>>>>
>>>>> HP's usually need the hplip and hpijs ppds. Throwing ing cups-pdf,
>>>>> gutenprint won't hurt either.
>>>>>
>>>>> V
>>>>>
>>>> It prints fine as long as I turn off the firewall.  I'm managing the
>>>> firewall using KDE's Guarddog GUI tool.  There is some protocol that
>>>> needs to be enabled for the dang thing to work.  Someone had mentioned
>>>> opening port 9100.
>>> I print to various network printers (HP included) from a firewalled 
>>> server. I have ipp (port 631) open for both tcp and udp.
>>> (wasn't that port mentioned already?)
>>> I have it configured with:
>>> Device URI: socket://hostname
>>> The hostname is resolvable via local dns. You could hard code an ip 
>>> address in its place if you like.
>>>
>> I opened port 631.  Nothing.
>> Then I opened 9100 and it printed.
>>
>> So 631 doesn't work. 631 & 9100 works. I'm too lazy to see if 9100 would
>> work.
> 
> 9100 is the port used by HP's internal print servers (JetPrint).
> 
> You should be able to print just fine with only 9100 enabled.
> 
> 631 is for CUPS servers and IPP printers, AFAIK none of the LaserJet's support IPP.
> 
> You may still want to open 631 on the localhost interface just so you can more easily manage the CUPS server on your box (if you open localhost:631 in a browser, you'll usually get a CUPS management interface).
> 
> 

I sit corrected. I have 631 open for cups access. socket: (JetDirect) 
protocol uses port 9100. I think that as long as you have something to 
the effect of:
-A RH-Firewall-1-INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
in your firewall chain then printing should work without specifying a 
port, because the packets from the printer are part of an established 
session (initiated by your computer). Providing your firewall isn't 
blocking outbound packets that is.

-- 
-Eric 'shubes'