Saturday, April 23, 2005

Review of the Slashdot discussion of CUPS

The following is a review of a discussion which took place on the slashdot forum. I've summarized some of the postings into what I think is useful for working with CUPS.

I've been struggling with setting up a new laptop and getting it to talk to my print server, using Fedora Core 3, and nothing seems to have changed -- the admin items for adding a printer are exactly as Eric described them back then -- unclear, confusing, and no where near as friendly as their Win* equivalents. Definitely not something I'd expect my Aunt Ethel to be able to figure out. What's going on here?

For those who are still frustrated with the CUPS GUI, how would you improve it?


By using Mac OS X's interface to CUPS. [apple.com]

The hardest part of setting up a printer using CUPS under Debian was knowing that I had to point my browser at http://localhost:631/ [localhost]. After that, what's so hard about clicking on Printers, Add Printer, then select the make and model?

Mandr{ake,iva}'s printer admin thingie actually runs nmap to sniff your network and find all printers exported by all machines using any protocols it knows how to talk. It's pretty amazing, but it took 10 minutes or more to run on the building network here, during which time the GUI didn't repaint and appeared hung.

I would have killed it in disgust, thinking it really was hung, but first I did a "top" to see if I could tell what it was doing. Then my jaw dropped when I saw it running nmap and starting and stopping many other processes to try to connect to the open ports it was finding, so I let it finish and was fairly impressed. It really needs a progress bar, or better, to have printers pop up in the GUI as they are found.

Fedora's printer config dialog sucks -> Linux printing status: unfriendly.

I'm partial to the KDEPrint system [kde.org], and wish that it was half as easy to configure network printers in Windows as it is through the nice KDE GUI.

Not long ago, there was a Slashdot review [slashdot.org] of a certain book [oreilly.com], which included a chapter on CUPS that can be downloaded for free [oreilly.com] (can't beat that price!). It seems to demystify the entire process of administering CUPS.

The reason some printers work on OS X and not on Linux is because CUPS allows running binary print filters.

Many printer manufacturers use Carbon filters for OS X. Game over.

CUPS is a full featured RIP and postscript processor. It does support arbitrary binary printing, however, and this is exactly what happens when you print to cups from windows via samba. Please see the cups documentation [samba.org].

If cups is just a "dumb spooler", explain lease how the heck it can print pdf, jpeg, hp-gl, tiff, and hundreds of other formats directly to your postscript printer?

If you don't have a postscript printer, yes, you must use a ppd that calls a intermediary driver (e.g., hpijs) that cups just passes the job to.

forget the CUPS application tools, user http://localhost:631. The www interface at least works all the time.

Wednesday, April 20, 2005

Why Aren't More Distros Becoming LSB Certified?

Slashdot has a good discussion on wether Linux needs a standards base or not and what the costs/benefits are. Good discussion.

Monday, April 18, 2005

setting up DNS Server Resolution & /etc/resolv.conf

With Comcast's recent problems with their DNS servers and the spat of DNS server poisonings going around, I thought it would be a good idea to cover how to configure DNS servers within Linux and which files to configure.

DNS servers are what allow normal people to find web pages by typing in website names and having those anmes associated with an actual server located somewhere else in teh world.

The main file within Linus used for DNS resolution is the /etc/resolv.conf file. Servers that are checked for DNS settings are listed in this file. The format is similar to the following:
nameserver 208.164.186.1
nameserver 208.164.186.2
Each nameserver will be checked in the order they are listed here. The nameserver entry tells the IP address of the host to use for DNS queries. If it is set to 127.0.0.1 (which is the default) then the local name daemon is used that may use the /etc/hosts database to translate host names. The default nonamed name server can't look beyond the local network.

Here is a listing of DNS servers which you can plug in whenever you might be having problems:Some DNS servers I reccomend:
4.2.2.1 4.2.2.2 4.2.2.3
4.2.2.4 4.2.2.5 4.2.2.6
These are all DNS server addresses that resolve differently across the country.

dadkins See Profile adds these DNS servers:
SpeakEasy Nameservers
66.93.87.2 216.231.41.2 216.254.95.2
64.81.45.2 64.81.111.2 64.81.127.2
64.81.79.2 64.81.159.2 66.92.64.2
66.92.224.2 66.92.159.2 64.81.79.2
64.81.159.2 64.81.127.2 64.81.45.2
216.27.175.2 66.92.159.2 66.93.87.2

ORSC Public Access DNS Nameservers
199.166.24.253 199.166.27.253 199.166.28.10
199.166.29.3 199.166.31.3 195.117.6.25
204.57.55.100

Sprintlink General DNS
204.117.214.10 199.2.252.10 204.97.212.10

Cisco
128.107.241.185 192.135.250.69