Subject: Move the complete session dir (NX_ROOT) to local file space
From: Mike Gabriel <[email-masked]>
To: [email-masked]
Cc: [email-masked]
Date: Thu, 26 Jun 2014 23:14:29 +0000

Package: x2goserver
Severity: important

Hi all, hi Alex,

we got feedback about NX and NFS that makes me think we should move  
the server-side session dir completely to local file space, e.g.

/tmp/.x2go-$USER/C-<sessionid>

and only leave a symlink behind at its current location:  
~/.x2go/C-<sessionid> ---> /tmp/.x2go-$USER/C-<sessionid>

Read about deftjack's experience with NX below (thanks to "deftjack"  
for allowing me quoting the discussion).

Mike

""" [discussion on #x2go at irc.freenode.net (2014-06-26)]
23:06 < deftjack> So I have a full blown desktop on the system and it  
still crashes.
[...]
23:36 < deftjack> well its something to do with the nfs home directories.
23:48 < deftjack> In NX you could tell it to use an alternate home  
directory for users. Can you do that with x2go?
23:49 < deftjack> One reason I did that with NX was to get the session  
info off nfs and on the local box.
23:49 < deftjack> It made things far more stable.
23:49 < deftjack> And faster.
[...]
23:58 < deftjack> It was "UserNXDirectoryPath" in the node.cfg on NX.
23:58 < deftjack> Basically it told it where it should put the users .nx dir.
23:59 < deftjack> at the nxserver/nxnode level.
23:59 < deftjack> I should be able to work around this by simply  
making the system not use nfs homes and they will just need to
                    be made when people are given ssh access.
23:59 < deftjack> but still use ldap auth.
[...]
00:27 <@sunweaver> deftjack: are you playing with X2GO Server from the  
nightly builds?
[...]
00:28 <@sunweaver> the nightly builds are currently broken due to a  
90%-baked commit of another developer...
00:28 <@sunweaver> feedback mails have been sent, no reaction, yet.
[...]
00:38 <@sunweaver> deftjack: the NX_ROOT is ~/.x2go/C-<sessionid>/ on  
the server.
00:39 <@sunweaver> deftjack: define "more stable" and define "and faster"...
[...]
00:51 < deftjack> sunweaver: If there was ever a disruption or even  
significant slow down in nfs NX would timeout on access to
                    its session info and peoples NX sessions would simply die.
[...]
00:51 < deftjack> sunweaver: Faster in that writing locally to the  
machine was faster than nfs even on a good day.
[...]
00:52 <@sunweaver> we actually should then consider moving NX_ROOT to  
/tmp/.x2go-$user/ completely...
00:52 < deftjack> Note we dont have crappy nfs here. Netapps but  
sometimes the servers would get hit hard and three would just be
                    this threshold that would cause NX issue.
00:52 <@sunweaver> ok....
00:52 < deftjack> sunweaver: So in NX they just allowed you to specify  
a different location for .nx on the nxnode(server side).
00:52 < deftjack> It worked perfectly.
00:53 < deftjack> I just put them all in /var/nxhome so user foo would  
have /var/nxhome/foo/.nx
00:53 <@sunweaver> this is very interesting information...
[...]
00:53 < deftjack> But still have access to their nfs mounted /home/foo
[...]
00:54 < deftjack> Ive also run into some selinux issues with their  
homes on nfs etc. Easily fixed but a pain.
[...]
00:55 <@sunweaver> deftjack: may I quote your information in a post on  
x2go-dev mailing list ?
00:55 <@sunweaver> because we have to get the NX_ROOT issue fixed for  
at least one file now, anyway...
[...]
01:07 < deftjack> sunweaver: absolutely.
01:07 <@sunweaver> thanks!
01:07 < deftjack> sunweaver: sorry at work, disruptions...
"""
-- 

DAS-NETZWERKTEAM
mike gabriel, herweg 7, 24357 fleckeby
fon: +49 (1520) 1976 148

GnuPG Key ID 0x25771B31
mail: [email-masked], http://das-netzwerkteam.de

freeBusy:
https://mail.das-netzwerkteam.de/freebusy/m.gabriel%40das-netzwerkteam.de.xfb