[cups] [UNKN] STR #4320: Strange problem with CUPS on a Linux (CentOS 5.10) LAN

[Michael Sweet]

Firewall?


Sent from my iPad

> On Dec 22, 2013, at 12:38 AM, Robert Heller <heller at deepsoft.com> wrote:
> 
> At Sat, 21 Dec 2013 19:13:35 -0500 Michael Sweet <msweet at apple.com> wrote:
> 
>> 
>> 
>> Robert,
>> 
>>> On Dec 21, 2013, at 5:59 PM, Robert Heller <heller at deepsoft.com> wrote:
>>> ...
>>> I'm off as well.  We are stuck at 1.3.7, since that is the version supplied by 
>>> RHEL/CentOS 5.  If browsing is dropped, how does printer sharing via cups 
>>> work?  Do you have to explicitly configure the shared printers?  Why was 
>>> browsing dropped?
>> 
>> Bonjour (DNS-SD) is used exclusively in 1.6 and later and was available as far back as 1.1.17 (assuming your OS vendor enabled it).
>> 
>> Browsing was dropped because the simple heartbeat broadcasts used by CUPS
>> browsing were really bad for network performance (particularly on wireless
>> LANs), it only worked with IPv4, it didn't like network changes, and it
>> needed either hardcoded IPs or working DNS. Bonjour doesn't have that
>> problem and, for larger network installs, you can use regular DNS (vs.
>> multicast DNS) fairly easily.
> 
> The machine has always had a hard-coded IPv4 address.  We only ever use 
> regular DNS.
> 
>> 
>>> ...
>>> What sort of network configuration error that only affects *one* machine.
>> 
>> Address configuration issues come to mind - a bad interface address,
>> broadcast address, or netmask will cause problems with broadcast-based
>> protocols but often does not affect TCP-based protocols.
> 
> This is all via DHCP and all of that is correct.
> 
>> 
>>> The 
>>> diskless clients get the network set up via DHCP in the init ramdisk and they 
>>> all use the same init ramdisk, so either they are all wrong (in which case 
>>> none should work) or are all right (in which case they should all work).  With 
>>> only one have *intermittent* problems, it is strange.  As you suggested, a 
>>> *physical* network problem would cause other (very obvious) problems, which 
>>> don't *seem* to be happening.  The problem is very specific, which *suggests* 
>>> a specific problem, but nother pops up.
>> 
>> One possibility - was the machine (or the MAC address of the machine)
>> previously associated on the network with a different address? Then the DHCP
>> server might be handing it an old address instead of an address from the
>> current space?
> 
> No, all of that is sane.  I did change the address from one address to 
> another. The problem vanished, but came back.
> 
>> 
>> _________________________________________________________
>> Michael Sweet, Senior Printing System Engineer, PWG Chair
>> 
>> 
>> 
>> This message contains data in an unrecognized format, application/pkcs7-signature,
>> which is being decoded and written to the file named "/home/heller/Mail/Attachments/423-smime.p7s".
>> If you do not want this data, you probably should delete that file.
>> Wrote file /home/heller/Mail/Attachments/423-smime.p7s
> 
> -- 
> Robert Heller             -- 978-544-6933 / heller at deepsoft.com
> Deepwoods Software        -- http://www.deepsoft.com/
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