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

[Robert Heller]

At Sun, 22 Dec 2013 11:59:09 -0500 Michael Sweet <msweet at apple.com> wrote:

> 
> Firewall?

There is none on the LAN. The diskless clients don't run iptables at all and
the server has two NICs and functions as a firewall router to the non-LAN NIC
to the outside Internet. Actually I run a 'standard' RedHat IPTables firewall
on my Laptop, and it has no problem seeing the shared printers, either at the
library or on my home LAN (my office Desktop also runs as a firewall router,
but to a PPP connection, using a dialup analog modem as the 'public' Internet
connection).

> 
> 
> 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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> > 
> > 
> 
>                                                                                                                             

-- 
Robert Heller             -- 978-544-6933 / heller at deepsoft.com
Deepwoods Software        -- http://www.deepsoft.com/
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