Hi Mike,
2014-03-31 4:25 GMT+08:00 Mike Gabriel <[email protected]>: > Hi Frenklin, > > > On So 30 Mär 2014 16:46:45 CEST, Franklin Weng wrote: > >>> Was that login on another client on the Debian Edu network that failed or >>> user/admin login on TJENER? >>> >> >> On tjener. > > > Hmmm... ok. Then KDC would normally not notice that (because the times on > client and server (same machine) are identical). Maybe there indeed is some > timestamp issue in recent OpenLDAP versions that I have not stumbled upon, > yet. Under this condition I could even not see correct uid/gid in /skole/tjener/home0. For example, my own home directory should be at /skole/tjener/home0/franklin with uid/gid set to franklin/franklin. But under that condition (LDAP with future timestamp) in /skole/tjener/home0/ I saw the uid/gid of franklin is 1000/1000. If timestamp okay but unable to login after subnet_change, I could see uid/gid as franklin/franklin for /skole/tjener/home0/franklin. Another symptom was that, if LDAP was unusable, the login prompt of kdm will be delayed for several (up to 10) seconds. >>>> 3. The performance was not as good as our last test. We wondered if it >>>> was >>>> because of the quality of the LAN. One of the client could boot and >>>> logged >>>> into the system, but when operating (for example, browsing web pages or >>>> using some software) it disconnected with the main server, hence had >>>> problems writing configs back to home folder. >>> >>> >>> >>> Urgh... that is strange. Maybe DNS problems, as well. I noticed earlier, >>> that Debian Edu systems behave weirdly, if upstream (internet) DNS is >>> unavailable. Not sure why. >>> >> >> DNS worked that time I think. > > > Ok... > > >> Yesterday we went there again and was sure that LAN is gigabit and worked >> well. It means that we still didn't find out why. >> >> Another problematic scenario was that, the teacher asked (about nearly 30) >> students to download a video clip from youtube. Then 10 of them >> experienced >> network problem. They could no longer connect to anywhere until they >> rebooted. > > > A classroom full of youtube watchers is not a good idea, at all. But the > system should slow down, rather then break. > > Have you tried setting the NFSv4 options setup from sync to async? In > another post from Wolfgang Schweer I read today that there is such an issue > in the Debian Edu wheezy system. > I'll try it. >>>> 4. When clicking the menu icon, it would sometimes show the menu very >>>> slowly, maybe after 5 or more seconds. Also when I pointed the mouse to >>>> a >>>> category, it would sometimes show the second layer menu very slowly. >>>> Was >>>> it because the home folder was remotely mounted? Is there any way to >>>> improve this? >>> >>> >>> >>> This happens, because on first menu clicks the .desktop files are read >>> from disk/NFS. Next time, menus are obtained from the diskless client's >>> RAM >>> cache. You could try to read-ahead the .desktop files somehow. Could you please tell me more about "read-ahead"? I added a script reading all the .desktop and .directory files after logging into KDE. I put it in /etc/X11/Xsession.d/98read-ahead, using a nested for loop to read all desktop files under /usr/share/applications. (cat /usr/share/applications/kde4/dolphin.desktop > /dev/null 2>&1) However this morning the teacher told me that the speed showing the menu items was still the same. >> >> Thanks for the information. >> >> BTW, I tried to improve NFS performance in a gigabit environment but >> didn't >> know where to put NFS parameters. Could you please tell me how to improve >> NFS performance ? > > > On the server (TJENER) it is /etc/exports (of course). > > For the clients, you have to dive into the LDAP DIT (use ldapvi for it and > set env var VISUAL=<editor-of-my-choice>). > > The command line for me is > > VISUAL=mcedit ldapvi --discover -D > cn=admin,ou=ldap-access,dc=skole,dc=skolelinux,dc=no > > The original bootstrapping of those LDAP objects responsible for AutoFS > mounts is derived from these files [1]. Search for the corresponding entries > in your LDAP data. > > Mike > > [1] > http://anonscm.debian.org/viewvc/debian-edu/branches/wheezy/debian-edu-config/ldap-bootstrap/autofs.ldif?view=markup > > PS: your mail client seems to break mail quoting when viewing the mail in > plain text. Not sure if you post your mails as HTML or plaintext, but you > may consider sending plain text mails (if you don't do that already). Sorry. I used gmail all the time (including on my phone) but didn't change the default option (HTML). I changed to plain text mode this time. Franklin -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected] Archive: https://lists.debian.org/CADtxYXbr+FD=_L-sWZyPeihwYPYtLaLHdtROZvqvT5W_=zr...@mail.gmail.com
