I'm not sure if this will help but it can't hurt. I wrote this tiny C program to automate testing my thin client network. All you need to do is compile it and then run it as root. Root is required for ping to work in flood mode. 1) save the code below as a file. Say nettest.c *make sure the last line is blank 2) $gcc nettest.c -o nettest 3) #./nettest or you can save your output to a file like this #./netstat > outputfile //============================ <div style="direction: ltr;"> // A little utility to check thin client LTSP network #include <stdio.h> #include <stdlib.h> #include <string.h> int main() { FILE* fp=popen("netstat -t -e|grep x11|sed -e 's/:/ /g'|\ awk '{print $6}'|grep -v root|sort|uniq","r"); char ip[64]; while ( fgets(ip,sizeof(ip)-1,fp) ) { char ping[64]="ping -c200 -f -p aa "; system( strcat(ping,ip) ); } pclose(fp); return 0; } //=============================== </div> <div>On 9/7/06, <a href="mailto:dahopkins@comcast.net">dahopkins@comcast.net</a> <<a href="mailto:dahopkins@comcast.net">dahopkins@comcast.net</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">David, On my opteron system, still have the nscd issue. Also, we have students logging on/off alot. Without nscd it just becomes a real nightmare. Of course, currently I can't tell the difference. I can try a boot with the options you mention, but the console seems fine. As for video/sound, I haven't gotten far enough to even have those issues. Sounds works (first person only though, known issue, resolved with latest ltsp patches), not sure if sound/video will stay synced up. <begin whining> The support for usb devices and sound are the entire reason we upgraded to this version -- we have 4 teachers that are vocally demanding that sound/video work or else it is back to Windows. Have a couple of weeks to get it fixed and then this issue crops up. <end whining> Anyhow, the latest was that around 3pm thin clients just quit booting from the system with the NFS mount issue. tftp <a href="http://et.al">et.al</a>. were running, so I rebooted the box and everything came back up. Tomorrow (Friday) I will start using ntop/sar/tcpdump to see if I can get some kind of handle on what the real issue is. Of course I only have a couple of hours in the morning before I have to be at another school to assist with some work there. Ran dmesg and nothing jumped out at me. All the hardware was recognized, no warnings/issues. Thanks though for the suggestion, I will see if the tech teacher is up to an experiment with it. Sincerely, Dave Hopkins -------------- Original message ---------------------- From: "David Trask" <<a href="mailto:dtrask@vcsvikings.org">dtrask@vcsvikings.org</a>> > There was an nscd bug that caused it to die....I'm not sure if it got > fixed....I suspect it did. When it happened though I found that turning > off nscd solved the issue...and we've also found that unless you have a > LOT of users, it's unnecessary. also...as for the slow server...I had one > with a hardware conflict that suddenly cropped up in FC4 (previous > versions were fine) I had to add "noapic" and "noapci" to the grub file > menu.lst to get it to run right. In FC5 the problem seems to be better, > but not solved....so I just got a new server yesterday just like the one > that I'm NOT having hardware issues with (made sure)....so I am > "reprovisioning" it....the new server becomes the K12LTSP box and the > older one becomes the Windows Terminal server. LOL Anyway....are you > experiencing things like sluggish video....slow dialog boxes...and so > forth even when actually on the server? If so it could be a hardware > conflict. > > > "Support list for open source software in schools." <<a href="mailto:k12osn@redhat.com">k12osn@redhat.com</a>> > writes: > >> > >> The high bandwidth usage is an obvious candidate. Any idea on what is > >> chewing up the bandwidth? > > > >Not really, usage patterns/programs for the teachers/students haven't > >changed much year-to-year. Software packages are the same as last year. > >Only change was FC5 upgrade. (mb is Supermicro X5DP8-G2 in case that > >matters somehow) > > > >> > >> I would also check for authentication/authorization issues (I note in > >> the archives that you use LDAP). > > > >Yep, used David Trask's instructions originally, updated with Matt's > >script later. Nothing changed though in last year. > > > >> > >> Double-check that all of the LDAP configs are correct. > >> > > > >Everything is as it should be. Haven't upgraded to latest samba though > >because of concerns with the latest/greatest version of samba and the > >traffic on the samba list about it. > > > >> Make sure that nscd is running (/sbin/service nscd status) > >> > > > >Have had an ongoing issue with nscd since like forever. I am using a > >dual-Opteron server with the prior version of K12LTSP running (x86_64). > >Fully patched, but I have not upgraded the system to the FC5 version. > >nscd still dies 2-3 times each day. A simple restart, or at worse clear > >the database files and restart resolves the issue (on site tech teacher > >has a script that he runs if he sees the authentication stop). I am > >planning to move my LDAP server to a new 32-bit system just to get away > >from this issue. > > > >> Make sure that DNS is correct (/etc/resolv.conf) > >> > > > >Haven't touched this either, but will recheck. > > > >> > >> I'd also check the disk sub-system... > > > >I did upgrade from Ultra160 IBM Deathstar drives (they were dirt cheap > >and now I know why) to Ultra320 Seagate Barracuda's. Was using a > >zero-channel controller for RAID-1 on the OS drives, but ... that is > >another thread. :) Now using software RAID-1 on one system, nothing on > >the other (skating on thin ice). Both systems show the same issues. > > > >> > >> Run "dmesg" and look for SCSI errors > >> > >Haven't seen any so far. Checked earlier, will check again. > > > >> Run "sar -b" to see the disk I/O usage patterns > >> (if you don't have "sar", install it with "yum install sysstat") > >> > >have to install and test this as well. Only issue is that I am running > >out of annual leave to spend at the school troubleshooting this. The > >issues only show up under load. Still, will be there tomorrow morning > >bright and early since it is my day off :) > > > >Sincerely, and thankfully, > >Dave ... > > > >_______________________________________________ > >K12OSN mailing list > ><a href="mailto:K12OSN@redhat.com">K12OSN@redhat.com</a> > ><a href="https://www.redhat.com/mailman/listinfo/k12osn"> https://www.redhat.com/mailman/listinfo/k12osn</a> > >For more info see <<a href="http://www.k12os.org">http://www.k12os.org</a>> > > > > David N. Trask > Technology Teacher/Director > Vassalboro Community School > <a href="mailto:dtrask@vcsvikings.org">dtrask@vcsvikings.org</a> > (207)923-3100 > > > _______________________________________________ > K12OSN mailing list > <a href="mailto:K12OSN@redhat.com">K12OSN@redhat.com</a> > <a href="https://www.redhat.com/mailman/listinfo/k12osn">https://www.redhat.com/mailman/listinfo/k12osn</a> > For more info see <<a href="http://www.k12os.org"> http://www.k12os.org</a>> _______________________________________________ K12OSN mailing list <a href="mailto:K12OSN@redhat.com">K12OSN@redhat.com</a> <a href="https://www.redhat.com/mailman/listinfo/k12osn"> https://www.redhat.com/mailman/listinfo/k12osn</a> For more info see <<a href="http://www.k12os.org">http://www.k12os.org</a>> </blockquote></div> -- Robert Arkiletian Eric Hamber Secondary, Vancouver, Canada Fl_TeacherTool <a href="http://www3.telus.net/public/robark/Fl_TeacherTool/">http://www3.telus.net/public/robark/Fl_TeacherTool/</a> C++ GUI tutorial <a href="http://www3.telus.net/public/robark/">http://www3.telus.net/public/robark/ </a>