XROOTD-L Archives

Support use of xrootd by HEP experiments


Options: Use Forum View

Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
"Langston, Matthew David" <[log in to unmask]>
26 Feb 2005 11:55:48 -0800Sat, 26 Feb 2005 11:55:48 -0800
text/plain (87 lines)
Hi Peter,

My ROOT installation is the simply the standard v4.02.00 win32gdk tarball directly from the ROOT site. I haven't made any customizations, so maybe this is a ROOT problem as you suggest?

This is a Java xrootd client written by Tony. It supports a small subset of xrootd commands (dirList, login, ping, stat, open, read and close) - just enough so that we could read histograms and trees for GLAST. We plan on making much more extensive use of xrootd in the future, and Tony and I have talked about wanting to move to Alvise Dorigo's Java xrootd client, but neither of us has looked into Alvise's code in enough detail to know how to proceed yet.


-----Original Message-----
From: Peter Elmer [mailto:[log in to unmask]] 
Sent: Saturday, February 26, 2005 11:30 AM
To: Langston, Matthew David
Cc: xrootd-l; Gerardo Ganis
Subject: Re: anonymous ROOT client trouble with simple xrootd setup

  Hi Matt,

On Sat, Feb 26, 2005 at 11:17:42AM -0800, Langston, Matthew David wrote:
> I know this configuration works because I am able to read ROOT files
> (histograms, trees, etc.) using our Java xrootd client. However, when
> I try to use the ROOT 4.02.00 command line I get this error from ROOT:
> root [0] myfile myfile = TFile::Open("root://glast01.slac.stanford.edu//nfs/farm/g/glast/u07/mcenery/systests/GlastRelease/v6r2p1/VerticalGamma100MeV/linux/VerticalGamma100MeV_Histos.root");
> Error in <TWinNTSystem::SendRaw>: cannot send buffer
> Info in <TAuthenticate::Authenticate>: attempted methods SSH/UidGid are not supported by remote server version
> Info in <TAuthenticate::Authenticate>: failure: list of attempted methods: UsrPwd SSH UidGid
> Error in <TPSocket::Authenticate>: authentication failed for [log in to unmask]
> Error in <TNetFile::TNetFile>: can't open connection to rootd on host glast01.slac.stanford.edu at port 1094
> Error in <TNetFile::Create>: authentication attempt unsuccessful
> root [1]

   I don't have any experience with using the TXNetFile client on Windows.
There were some outstanding issues, but I don't recall if they've been dealt
with yet. Maybe Gerri or Fabrizio can comment.

  One thing that is clear above is that you are not getting the right client
from the root plugin manager (i.e. you got the old TNetFile instead of the
new TXNetFile). We should probably figure out why that is happening first.
>From etc/system.rootrc I would expect "root://" to default to TXNetFile
for all platforms. I don't see any platform ifdef's there, so something else
must be going wrong.

  I guess the java client is the one that Tony has mentioned in his CHEP


> And this is what I get in the xrootd log file:
> glast@glast01 $ tail -f /tmp/xrootd/xrdlog 
> 050226 10:44:11 3310 XrdLink: ?:45@ntvpn2-008 disconnected after 0:00:00 (matching protocol not found)
> 050226 10:44:12 3310 XrdLink: ?:45@ntvpn2-008 disconnected after 0:00:00 (matching protocol not found)
> In the ROOT stack trace, I see that it is trying to login as "[log in to unmask]". OK, so I try telling ROOT to use anonymous credentials using this:
> root [1] TAuthenticate::SetGlobalUser("anonymous");
> However, I get the same "authentication attempt unsuccessful" error, except that now the ROOT stack trace reports that "[log in to unmask]" is not authorized.
> What am I doing wrong? Is it a ROOT configuration problem (perhaps something needs to go into .rootrc), is it an xrootd configuration problem? What does the "matching protocol not found" mean in the xrootd log file? What protocol is it talking about - perhaps an authentication protocol that I need to configure?
> As I mentioned, our Java client is able to read ROOT files from our simple xrootd server without problems. Our Java client sends "anonymous" for the username and "langston@trinity" for the password. This is what I get from the xrootd log file when connecting using our Java client:
> glast@glast01 $ tail -f /tmp/xrootd/xrdlog 
> 050226 11:08:30 3310 XrootdXeq: User logged in as anonymou.12345:45@ntvpn2-008
> 050226 11:08:38 3310 XrdLink: Unable to receive from anonymou.12345:45@ntvpn2-008; connection reset by peer
> 050226 11:08:38 3310 XrdLink: anonymou.12345:45@ntvpn2-008 disconnected after 0:00:11 (link read error)
> Even though there is a "connection reset by peer" and a "link read error" message, the Java client is still able to read histograms and trees just fine.
> Any help on getting the ROOT command line to be able to read files from our xrootd server would be appreciated.
> Warmest regards, Matt

Peter Elmer     E-mail: [log in to unmask]      Phone: +41 (22) 767-4644
Address: CERN Division PPE, Bat. 32 2C-14, CH-1211 Geneva 23, Switzerland