[Yum] Yum fails spectacularly a lot - and I miss it.

[Michael Stenner]

On Tue, Dec 12, 2006 at 11:09:18AM -0700, Aaron Hawryluk wrote:
> Everything network-wise works - except yum. HTTP protocols work, ftp, samba,
> everything. Googling produced some blather about http proxies and something
> about chunked byte-transfer encoding not being supported by anonymous
> proxies, none of which made any sense on this network as (according to my
> sysadmin) there is absolutely no proxy whatsoever, anonymous or otherwise.

Your sysadmin is probably right, but I've seen crazy stuff before... 

> -d 255 doesn't seem to produce any useable debug info as far as the
> connection goes - maybe there are python scripts I can modify to produce
> meaningful output?  I know I'm not alone in this from my googling and I know
> the proxy issue hasn't resolved all the problems.  I can't even find a cvs
> repository to check out the code and modify for my own debugging needs. I'll
> have a look at ethereal as soon as I figure out how to make it work - I can
> set up servers, routers etc. But I'm really not a network back-end guy -
> TCP/IP stack traces give me the willies.

OK.  Start up ethereal (or ethereal-gnome or wireshark or whatever
it's called these days).  Go to Capture->Options.  In filter, type
"port 80" and hit start.  Now, go run yum.  When you're done, hit
"stop" and it will pop up packet analysis.  Puzzle through it for a
bit, but if that doesn't work, save it and send it to the list.  Be
sure to trim any passwords, etc.

Other things you can do it you really wanna dive in:

  http://bird.ece.arizona.edu/~mstenner/urlgrabber-20061212.tar.gz

Unpack that and cd into it.  Then do:

  export PYTHONPATH=.
  export URLGRABBER_DEBUG=DEBUG,ugdebug.txt
  yum <whatever yum options you use>

Then, look in "ugdebug.txt" for any hints.  Send that to the list,
too.

Note:  the current urlgrabber HEAD is broken if you have M2Crypto
installed, which you probably don't.  If you DO, then do this first
(from within the first urlgrabber directory:

  mkdir M2Crypto; touch M2Crypto/__init__.py

> Only lead I have so far - wget reports the size of the file as 367,266
> bytes. Yum reports the size of the file as 359 kB, or 367,616 bytes.  Is yum
> approximating size, or is the library it's using to download inserting CR/LF
> instead of just LF? Am I getting into "your system uses UTF-8 and it should
> use ISO-8859-1" territory? 

No.  That's unlikely.  I'm not ruling out a bug in urlgrabber, though.
The actual error you're getting is from the yum callback which
verifies the header info, though.  There could be a bug in that as
well.

> Me not know. It has to be network

It smells like network, but lets not assume.  Also try "yum clean
all".  In fact, do that first 'cause it's easy.

> , and yet other
> people within the network can run yum no problem. And I have no idea why ftp
> servers configured to support yum would report "Command not understood" -
> even if Yum was passing EPSV or something silly, those servers should
> obviously deal with whatever yum was passing.

the packet sniffer will inform that, too "port 20 or port 21".

					-Michael
-- 
  Michael D. Stenner                            mstenner at ece.arizona.edu
  ECE Department and Optical Sciences Center                520-626-1619
  University of Arizona                                         ECE 524G