August 2002 - WLUG - wlug.mailman3.com

Re: [Wlug] Stupid Hardware Clock Tricks, aka: WTF?

by Michael Frysinger

i run 2.4.1{6,8}-xfs w/out any time issues (so as to dispell the source of the problem being kernel) -mike ----- Original Message ----- From: "Theo Van Dinter" <felicity(a)kluge.net> To: "Worcester Linux User's Group" <wlug(a)wlug.org> Sent: Wednesday, August 21, 2002 17:31 Subject: [Wlug] Stupid Hardware Clock Tricks, aka: WTF? > Over this past weekend I upgraded my server from a P200/RedHat Linux > 7.2 to a new Athlon 850/RedHat Linux 7.3. The Athlon was my trusty > workstation for many a year. Everything's great, except for one problem: > the clock goes crazy! > > It seems to be a once per second issue: > > $ perl -e '$t=time;while(1){$t2=time; warn join("\n",scalar > localtime($t),scalar localtime($t2),"") if ($t2-$t>4); $t=$t2;}' > Wed Aug 21 17:17:28 2002 > Wed Aug 21 18:29:03 2002 > Wed Aug 21 17:17:29 2002 > Wed Aug 21 18:29:04 2002 > Wed Aug 21 17:17:30 2002 > Wed Aug 21 18:29:05 2002 > > > I use netsaint to monitor system health, and it keeps complaining about > the time jumps: > > Aug 21 18:28:03 eclectic netsaint: Warning: A system time change of 4296 > seconds (forwards in time) has been detected. Compensating... > Aug 21 17:16:31 eclectic netsaint: Warning: A system time change of 4293 > seconds (backwards in time) has been detected. Compensating... > Aug 21 18:29:42 eclectic netsaint: Warning: A system time change of 4296 > seconds (forwards in time) has been detected. Compensating... > Aug 21 17:18:10 eclectic netsaint: Warning: A system time change of 4293 > seconds (backwards in time) has been detected. Compensating... > > Of course, random checks start failing as well since they occasionally > run during the time jump, and if they're checking for time since something > occured (log entry, cron run, query response time, etc) ... > > I've tried "hwclock --systohc" to force the hardware clock to the same > time as the system, didn't help. I'm running NTP and thought maybe > it was having problems, so I tried turning that off, didn't help. > I went through BIOS and tweaked memory/IRQ settings -- I didn't think > it would really solve anything, but the setting changes and reboot kept > the behavior away for ~14-15 hours. > > > So I'm completely stumped as to what causes this problem. Has anyone > seen anything like this before? Any suggestions for things to look at? > I'm at the point where I'm planning to just buy a new bit of hardware, > migrate the drives and such again, and go from there. With my luck the > problem would follow me of course... :( > > Thanks in advance. :) > > BTW: If anyone is wondering, I'm running SGI's XFS patched 2.4.18 kernel: > 2.4.18-SGI_XFS_1.1. I'm thinking about dropping back to a 2.4.9 kernel > w/ XFS support and seeing if that works any better. :( I was running > 2.4.18 on the P200 for quite a while though without problem. > > -- > Randomly Generated Tagline: > I don't want to look like a weirdo. I'll just go with a muumuu. > > -- Homer Simpson > King-Size Homer > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug >

Aug. 21, 2002

Stupid Hardware Clock Tricks, aka: WTF?

by Theo Van Dinter

Over this past weekend I upgraded my server from a P200/RedHat Linux 7.2 to a new Athlon 850/RedHat Linux 7.3. The Athlon was my trusty workstation for many a year. Everything's great, except for one problem: the clock goes crazy! It seems to be a once per second issue: $ perl -e '$t=time;while(1){$t2=time; warn join("\n",scalar localtime($t),scalar localtime($t2),"") if ($t2-$t>4); $t=$t2;}' Wed Aug 21 17:17:28 2002 Wed Aug 21 18:29:03 2002 Wed Aug 21 17:17:29 2002 Wed Aug 21 18:29:04 2002 Wed Aug 21 17:17:30 2002 Wed Aug 21 18:29:05 2002 I use netsaint to monitor system health, and it keeps complaining about the time jumps: Aug 21 18:28:03 eclectic netsaint: Warning: A system time change of 4296 seconds (forwards in time) has been detected. Compensating... Aug 21 17:16:31 eclectic netsaint: Warning: A system time change of 4293 seconds (backwards in time) has been detected. Compensating... Aug 21 18:29:42 eclectic netsaint: Warning: A system time change of 4296 seconds (forwards in time) has been detected. Compensating... Aug 21 17:18:10 eclectic netsaint: Warning: A system time change of 4293 seconds (backwards in time) has been detected. Compensating... Of course, random checks start failing as well since they occasionally run during the time jump, and if they're checking for time since something occured (log entry, cron run, query response time, etc) ... I've tried "hwclock --systohc" to force the hardware clock to the same time as the system, didn't help. I'm running NTP and thought maybe it was having problems, so I tried turning that off, didn't help. I went through BIOS and tweaked memory/IRQ settings -- I didn't think it would really solve anything, but the setting changes and reboot kept the behavior away for ~14-15 hours. So I'm completely stumped as to what causes this problem. Has anyone seen anything like this before? Any suggestions for things to look at? I'm at the point where I'm planning to just buy a new bit of hardware, migrate the drives and such again, and go from there. With my luck the problem would follow me of course... :( Thanks in advance. :) BTW: If anyone is wondering, I'm running SGI's XFS patched 2.4.18 kernel: 2.4.18-SGI_XFS_1.1. I'm thinking about dropping back to a 2.4.9 kernel w/ XFS support and seeing if that works any better. :( I was running 2.4.18 on the P200 for quite a while though without problem. -- Randomly Generated Tagline: I don't want to look like a weirdo. I'll just go with a muumuu. -- Homer Simpson King-Size Homer

Aug. 21, 2002

Red Hat, Westford MA career day

by Tim Burke

FYI - we're having an open house next Wednesday. http://bostonworks.boston.com/events/openhouses/redhat.shtml

Aug. 20, 2002

Re: [Wlug] REMINDER: WLUG BBQ

by desdinova＠soupforare.net

On 17 Aug 2002 at 20:59, Andy Stewart wrote: > > HI everybody, > > The WLUG BBQ will be held on Thursday, August 22nd starting at 6 PM. > Directions to Doug Waud's house, a.k.a BBQ Central, can be found on > the WLUG website. > > Please RSVP if you plan to attend. I've received 3 or 4 RSVPs and I'm > sure there will be more people than that. We need to have an idea how > much food to purchase. Je responde. That's the correct RSVP, isn't it? I don't remember my french teachings :) Thanks James KB1FJQ

Aug. 18, 2002

REMINDER: WLUG BBQ

by Andy Stewart

HI everybody, The WLUG BBQ will be held on Thursday, August 22nd starting at 6 PM. Directions to Doug Waud's house, a.k.a BBQ Central, can be found on the WLUG website. Please RSVP if you plan to attend. I've received 3 or 4 RSVPs and I'm sure there will be more people than that. We need to have an idea how much food to purchase. WLUG will supply the standard BBQ fare and some soda and munchies. If you want beer or wine, you may BYOB and we'll have a way to keep it cold. Feel free to bring your own dessert or cold salad items if you so choose. Doug's house has a pool so bring towels and such! If you can think of anything else, let me know. Otherwise, I'll see you all on Thursday. Later, Andy -- Andy Stewart, Founder Worcester Linux Users' Group Worcester, MA USA http://www.wlug.org

Aug. 18, 2002

Kernel int-13 interface?

by Chuck Homic

Hey, this one goes out to all you kernel hackers out there. After 4 years, I've once again become interested in installing Linux on my HP OmniBook 300. Because it's an aswesome computer, and I think DOS 5 is a complete waste of its skill. [Background. The OB300 is a vintage 386-20, with a passive reflective 640x480 LCD display. Basically an oversize TI calculator running DOS] Anyway, from my first tests, I discovered that I can indeed boot the kernel using loadlin. But it immediately freaks out because it can't read (or even think about) my primary media... solid-state PCMCIA flash cards. Now, I briefly tried looking up some data on the OB300's PCMCIA chipset (I think the first standard was still being developed when this computer was made) and quickly decided that wasn't the route to go. And HP told me to go to hell when I asked. But DOS seems to work just fine using the int 13 interface to access the flash disks. So now my question... can I do that in Linux? I don't see any block device support (and most people would agree an int 13 block device would be stupid), but I think I can write one myself. All it would have to do is make the switch into real mode, call the int 13 interface, and then come back. Will Linux tolerate that? As far as I know, many drivers use a real mode interrupt on laptops to trigger their power saving capabilities (suspend, etc...), so I suspect it would be okay. Can anyone stop me before I go too far? Or should I go ahead and write this thing? -Chuck

Aug. 16, 2002

potential mailing list problems

by Frank Sweetser

Just a quick heads up - the WLUG mailing list server seems to be having some issues, and since I won't be around to fix it until Monday, it may not be stable over the weekend. I have a backup of the mailing list data, though, so nothing should be lost once things are all fixed up. -- Frank Sweetser fs at wpi.edu, fs at suave.net | $ x 18 Full-time WPI Network Engineer, Part time Linux/Perl guy | Soitainly. I was assuming that came with the OO-ness of it. -- Larry Wall in <199710011802.LAA21692(a)wall.org>

Aug. 15, 2002

Re: [Wlug] USB Support in Linux 2.4.18

by Andy Stewart

On Saturday 10 August 2002 10:10 pm, chuck wrote: > How can I tell if a specific USB device, in this case a removable USB > hard drive, is supported by my kernel? I know that Linux 2.4.18 has > "support" for USB devices. Does this mean all USB devices or just a > few? I would think that the OS talks to the USB controller via a series > of well documented commands and that its up to the controller to talk to > the specific USB device. > > Does this make sense, or is there more to it? > > Thanks, > Chuck Check this website: http://www.qbik.ch/usb/devices/ It has a list of USB devices supported by the kernel. In many cases, there are separate modules for USB devices. Hotplug (when it works) is supposed to load these modules automatically. In my personal experience, I have found USB support to be spotty and not always reliable. However, when it does work, it tends to work fairly well. I recently took my printer off of USB and put it back to the much more reliable parallel port and have had no problems since. Later, Andy -- Andy Stewart, Founder Worcester Linux Users' Group Worcester, MA USA http://www.wlug.org

Aug. 11, 2002

Firewall Stops Working...

by jose sanchez

> Hello: > > This is my first post to the list and I would like > to > know if anyone have experienced or heard of what's > happenning to my box. > > I have a RH7.2 box as a firewall running an iptables > script. The box has three NICs. One for a LAN, one > for > a DMZ, and one for the Internet connection running > dhcpcd to get an IP from a cable modem (isp: Road > Runner). Everything works fine but, after hours of > innactivity I cannot access the Internet from the > LAN. > I can do everything else (chat, ftp, ssh, ping, > traceroute, etc...) from the LAN to the outside > world. > > > I was thinking it might be something with the > expiration of the IP lease but I have a chain to > take > care of that: > > iptables -A INPUT -i $INTERNET -d udp -s > $DHCP_SERVER > \ > --sport 67 --dport 68 -j ACCEPT > > iptables -A OUTPUT -o $INTERNET -d udp -d > $DHCP_SERVER > \ > --dport 67 --sport 68 -j ACCEPT > > These chains should do it but unfortunately in order > for me to get the box back to normal I have to > restart > it and also restart the modem. > > Thank you in advance for your help. > > > > __________________________________________________ > Do You Yahoo!? > HotJobs - Search Thousands of New Jobs > http://www.hotjobs.com > ===== "An ounce of gold cannot buy an ounce of time." - Anonymous www.whmicro.com __________________________________________________ Do You Yahoo!? HotJobs - Search Thousands of New Jobs http://www.hotjobs.com

Aug. 11, 2002

Re: [Wlug] USB Support in Linux 2.4.18

by Wesley Allen

Chuck, most mass-storage devices are supported by the usb-storage module. Plug in the drive go to a shell and type "usbview" the list should have your drive there, and may tell you what driver it uses. Wes On Sat, 2002-08-10 at 22:10, chuck wrote: > How can I tell if a specific USB device, in this case a removable USB > hard drive, is supported by my kernel? I know that Linux 2.4.18 has > "support" for USB devices. Does this mean all USB devices or just a > few? I would think that the OS talks to the USB controller via a series > of well documented commands and that its up to the controller to talk to > the specific USB device. > > Does this make sense, or is there more to it? > > Thanks, > Chuck > > > > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > -- This message may be digitally signed. For my public key, e-mail me a request.

Aug. 11, 2002