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- 11225 messages
Re: [Wlug] reboot problem - Update
by Gregory Avedissian
Folks asked for an update on this, so here it is.
Original problem - Black screen on startup or reboot occurred about 25% of
the time, right after the grub menu. No hard drive activity, no boot, no
ssh. This problem has existed since I built the computer a year ago.
Newer problem - Hard lockups, especially when the load was heavy. I first
noticed this when I installed Gutsy on a spare partition. It also happened
a few times in Etch, but I was using a custom realtime kernel when it
happened. There were also a couple of spontaneous reboots.
Hardware - ASUS M2V motherboard, Ath. X2 3800, Kingston RAM, Enermax PSU,
some kind of GeForce 6200 with a fan that started getting noisy, Seagate
drive, all about a year old.
What I did -
Replaced the vid card with a slightly older GeForce, and since then, the
black screen has only occurred once or twice out of scores of reboots.
Got a power supply tester, and the 5V rail read 5.4V one of the times I
tested it. Contacted Enermax, and they told me to try a different power
supply before I RMA'd mine.
Got off the realtime kernel and went back to the stock Etch kernel. No
more lockups in debian.
Flashed the motherboard with the newest bios after reading that others
were having lockup problems with this board. It didn't help.
Got a new 350W SilverStone and put it in. Still getting lockups in Gutsy.
I believe that the spontaneous reboots are a result of the relative
placement of the power button and the wheeled leg of my office chair. I
moved the computer back a few inches after I saw the two of them meet
once. (Note for the interested builder - buttons on Coolermaster case
stick out and require only a light touch. I just built a computer for a
friend, and the buttons on the Antec case are recessed and not so easy to
press in.)
Put the Enermax back in, and everything seems to be fine as long as I stay
away from Gutsy and the power button. Thanks again to everyone for their help.
Greg
Dec. 18, 2007
REMINDER: Upcoming WLUG Meeting
by Andy Stewart
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
HI Everybody,
Our next WLUG meeting will be on Wednesday, 12-dec-2007, at 7:00 PM in
the Access Grid Room on the WPI campus in Worcester, MA USA.
At this meeting, we'll have Dan Walsh from RedHat as our guest speaker.
Dan will talk about SELinux.
First, Dan will give a quick overview of SELinux, followed by a
discussion of what's new with SELinux in Fedora 8. Dan will then hand
out SELinux live CDs of Fedora 8, from which he will present how to
write SELinux policy. This promises to be a great meeting that you won't
want to miss.
After the meeting, we'll head out for dinner at a local pizza restaurant.
See ya then!
Andy
- --
Andy Stewart, Founder
Worcester Linux Users' Group (http://www.wlug.org)
Chelmsford Linux Meetup Group (http://linux.meetup.com/393)
Amateur Radio: KB1OIQ
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (GNU/Linux)
Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org
iD8DBQFHXeT5Hl0iXDssISsRAggmAJ0RwVvLuUuHMMZSElq5lt8hCh4lOACfQraL
teVSJANE/lCW5eAlSSCXnSs=
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Dec. 11, 2007
Re: [Wlug] ISP/Router/Modem Ethernet communications
by Mike Frysinger
On Monday 03 December 2007, kstratton(a)fastmail.us wrote:
> It is looking like the solution is one of the following:
>
> 1) Buy a new DSL modem that sopports 10 and 100 base T (I think I saw
> one at best buy, mine only supports 10 base T)
> 2) Buy a router that I can put linux on so that I can configure the
> router for 10 base T.this sounds like fun, but the likelyhood of
> eventually breaking it is great.
> 3) Buy both a new modem and router. I am confident that my equipment
> predated the gigabit standard release, so this is not a totally
> irrational solution (based on the autonegotiation standards).
> 4) Ignore the issue and kickstart the connection again if the problem
> re-occurs.
>
> My guess is on #4 for now, but #1 then #2 or #3 is still a possibility.
>
> Thank you everybody for your help. My biggest issue was not realizing
> that this kind of autonegotiation issue is not very unusual. I REALLY
> dislike it when I call tech support and my equipment is at fault.
what kind of modem is it ? ive collected a few dsl modems that are just
gathering dust in my basement.
-mike
Dec. 4, 2007
Re: [Wlug] ISP/Router/Modem Ethernet communications
by kstrattonï¼ fastmail.us
My initial problem was that I lost all connectivity with my router
connected to the DSL modem. this was after my setup worked consistently
for over 9 months. I was on the phone for over 4 hours total (2
sessions, the first one blamed it on an outage). The ISP technicians
can "see" the modem when I was having this problem and confirmed my
setup of the router. All the LEDs were positive (green). The ISP
technician then asked for me to connect the modem directly to the
computer. Various things were tried, including powering down the modem
and computer. Still no connection (ping would not work). The last
thing tried was to force the computer to talk to the mode at 1/2 duplex
10 base T and try to connect. This seemed to kickstart everything and
everything now works with the router or directly to the PC.
This may also seem to be a coincidence, but this problem happened about
a week and a half after changing the terms on my DSL service (cheaper
bundle).
It is looking like the solution is one of the following:
1) Buy a new DSL modem that sopports 10 and 100 base T (I think I saw
one at best buy, mine only supports 10 base T)
2) Buy a router that I can put linux on so that I can configure the
router for 10 base T.this sounds like fun, but the likelyhood of
eventually breaking it is great.
3) Buy both a new modem and router. I am confident that my equipment
predated the gigabit standard release, so this is not a totally
irrational solution (based on the autonegotiation standards).
4) Ignore the issue and kickstart the connection again if the problem
re-occurs.
My guess is on #4 for now, but #1 then #2 or #3 is still a possibility.
Thank you everybody for your help. My biggest issue was not realizing
that this kind of autonegotiation issue is not very unusual. I REALLY
dislike it when I call tech support and my equipment is at fault.
On Mon, 3 Dec 2007 12:18:24 -0500, "John Stoffel" <john(a)stoffel.org>
said:
>
> kstratton> Thank you everybody for your replies. I now know that this
> kstratton> autonegotiation issue can be potentially be a much bigger
> kstratton> problem with 100 base T than I thought. Specifically,
> kstratton> there is no defined mechanism in the spec to autonegotiate
> kstratton> for 100 base T cards. If I actually have time for this, I
> kstratton> guess I will have to find the spec and read it...
>
> Don't bother, it's not going to help you really. Just recognize that
> you can see auto-neg issues and keep it in mind when trouble shooting
> problems.
>
> kstratton> My network driver (windows) is a "NVIDIA nForce MCP
> kstratton> Networking Controller". It is an integrated network
> kstratton> connector on a HP pavilion. I do not know of a windows
> kstratton> equivalent to lspci, so I cannot get the actual reported
> kstratton> hardware rev. Maybe I have to get a good live CD distro.
>
> Hmm... I thought you were having auto-neg problems between your PC and
> the cable modem, you never said you had a Router in there. At least I
> don't remember and it's monday and I'm not good at memory... :]
>
> kstratton> In this case, resetting the cable modem did not fix the
> kstratton> problem, although it may have fixed it in the past.
>
> kstratton> My router is a four port Linksys Router about 5 to 8 years
> kstratton> old. My modem is a Speedstream 5280. I am sufficiently
> kstratton> annoyed by this problem to consider buying a new router if
> kstratton> this router has a force 10 base T option for the WAN. I am
> kstratton> willing to listen to any suggestions.
>
> So just to rehash the problem, you are seeing problems between the
> router and the cable modem, or between the router and the PC?
>
> Ok, so I just re-read your initial post and it sounds like you pulled
> the Router out of the mix when debugging with your ISP. What was the
> initial problem that had you remove the Router? What were the
> symptoms?
>
> It could simply be that one of the hardware boxes is getting flaky and
> starting to fail. But we need more information to really help.
>
> I've got an old Motorola Cable Modem (bought my own replacement) which
> I'd be willing sell/lend if need be. I think it's a 3200 something or
> other. Don't remember off hand. I'm with Charter, which might be an
> issue.
>
> Good luck,
> John
> _______________________________________________
> Wlug mailing list
> Wlug(a)mail.wlug.org
> http://mail.wlug.org/mailman/listinfo/wlug
--
kstratton(a)fastmail.us
Dec. 4, 2007
Re: [Wlug] ISP/Router/Modem Ethernet communications
by John Stoffel
kstratton> Thank you everybody for your replies. I now know that this
kstratton> autonegotiation issue can be potentially be a much bigger
kstratton> problem with 100 base T than I thought. Specifically,
kstratton> there is no defined mechanism in the spec to autonegotiate
kstratton> for 100 base T cards. If I actually have time for this, I
kstratton> guess I will have to find the spec and read it...
Don't bother, it's not going to help you really. Just recognize that
you can see auto-neg issues and keep it in mind when trouble shooting
problems.
kstratton> My network driver (windows) is a "NVIDIA nForce MCP
kstratton> Networking Controller". It is an integrated network
kstratton> connector on a HP pavilion. I do not know of a windows
kstratton> equivalent to lspci, so I cannot get the actual reported
kstratton> hardware rev. Maybe I have to get a good live CD distro.
Hmm... I thought you were having auto-neg problems between your PC and
the cable modem, you never said you had a Router in there. At least I
don't remember and it's monday and I'm not good at memory... :]
kstratton> In this case, resetting the cable modem did not fix the
kstratton> problem, although it may have fixed it in the past.
kstratton> My router is a four port Linksys Router about 5 to 8 years
kstratton> old. My modem is a Speedstream 5280. I am sufficiently
kstratton> annoyed by this problem to consider buying a new router if
kstratton> this router has a force 10 base T option for the WAN. I am
kstratton> willing to listen to any suggestions.
So just to rehash the problem, you are seeing problems between the
router and the cable modem, or between the router and the PC?
Ok, so I just re-read your initial post and it sounds like you pulled
the Router out of the mix when debugging with your ISP. What was the
initial problem that had you remove the Router? What were the
symptoms?
It could simply be that one of the hardware boxes is getting flaky and
starting to fail. But we need more information to really help.
I've got an old Motorola Cable Modem (bought my own replacement) which
I'd be willing sell/lend if need be. I think it's a 3200 something or
other. Don't remember off hand. I'm with Charter, which might be an
issue.
Good luck,
John
Dec. 3, 2007
Re: [Wlug] ISP/Router/Modem Ethernet communications
by Conner Finlay
I've got a Linksys WRT54GL which in my opinion is a great router for the
price. I then flashed it with dd-wrt. Here is a list of routers which can
support it.
http://www.dd-wrt.com/wiki/index.php/Supported_Devices
-Conner
On Dec 1, 2007 6:39 AM, <kstratton(a)fastmail.us> wrote:
> Thank you everybody for your replies. I now know that this
> autonegotiation issue can be potentially be a much bigger problem with
> 100 base T than I thought. Specifically, there is no defined mechanism
> in the spec to autonegotiate for 100 base T cards. If I actually have
> time for this, I guess I will have to find the spec and read it...
>
> My network driver (windows) is a "NVIDIA nForce MCP Networking
> Controller". It is an integrated network connector on a HP pavilion. I
> do not know of a windows equivalent to lspci, so I cannot get the actual
> reported hardware rev. Maybe I have to get a good live CD distro.
>
> In this case, resetting the cable modem did not fix the problem,
> although it may have fixed it in the past.
>
> My router is a four port Linksys Router about 5 to 8 years old. My
> modem is a Speedstream 5280. I am sufficiently annoyed by this problem
> to consider buying a new router if this router has a force 10 base T
> option for the WAN. I am willing to listen to any suggestions.
>
>
>
> On Fri, 30 Nov 2007 16:29:17 -0500, "John Stoffel" <john(a)stoffel.org>
> said:
> >
> > kstratton> I just went through some painful debug session(s) with my
> > kstratton> ISP. For some reason, after forcing 10 base T half duplex
> > kstratton> through my windows box directly to my modem (I do not
> > kstratton> expect ISPs to support linux),everything suddenly worked
> > kstratton> (after reconnection and re-enabling of course).
> >
> > Can you give more details on the cable modem box you're using and the
> > PC as well? Such as what network card in the PC you are using?
> >
> > kstratton> How often does this kind of thing happen? I have seen this
> > kstratton> kind of thing before only once before, and I was using an
> > kstratton> old hub that only supported 10 base T, not a home router
> > kstratton> that is supposed to autodetect the port type. I remember
> > kstratton> that the modem only supports 10 base T, but I am not 100%
> > kstratton> certain.
> >
> > Sun and Cisco were notirious for having problems figuring our
> > autonegotiation on the Sun hme (Happy Meal Ethernet) cards. They'd
> > end up 100Full on one side and 100 Half Duplex on the other. It would
> > work, just very slowly...
> >
> > kstratton> Does anybody have an explanation of what most likely
> > kstratton> happened? Do not hesitate to skimp on technical details or
> > kstratton> references if is convenient. I desperately want to
> > kstratton> understand what happened. --
> >
> > Something didn't autonegotiate properly. Did you try powering off
> > both devices and then powering them on starting with the cable box?
> >
> > Also, alot of Cable Companies lock the cable box to the first MAC
> > (ethernet hardware address) they see coming over the link. So if you
> > boot up with a PC, and then try to move to something else like a NAT
> > box or a linux box acting as a NAT box, things can go wonky.
> >
> > Usually a hard reset of the Cablemodem will do the trick, but
> > sometimes you need to contact the ISP and ask them to reset it for
> > you.
> >
> > In your case, it really sounds like a problem with Autonegotiation.
> > Some devices just don't do a good job, esp older equipment from before
> > the Gigabit ethernet stage.
> >
> > Just to expand on Frank's email, the people who designed the Gigiabit
> > Ethernet standard over Copper (802.xxx I can't remember) saw all the
> > problems with the 100/10 devices and autonegotiation and explicity
> > made AutoNeg part of the spec in a very well detailed way, so that
> > these problems won't happen again. As a matter of fact, Gigabit ports
> > are much smarter and don't require crossover cables either, you can
> > just plug them into back to back, they figure out what's going on
> > automatically and adjust.
> >
> > The joys of big ASICs!
> >
> > John
> > _______________________________________________
> > Wlug mailing list
> > Wlug(a)mail.wlug.org
> > http://mail.wlug.org/mailman/listinfo/wlug
> --
>
> kstratton(a)fastmail.us
>
> _______________________________________________
> Wlug mailing list
> Wlug(a)mail.wlug.org
> http://mail.wlug.org/mailman/listinfo/wlug
>
Dec. 1, 2007
Re: [Wlug] ISP/Router/Modem Ethernet communications
by kstrattonï¼ fastmail.us
Thank you everybody for your replies. I now know that this
autonegotiation issue can be potentially be a much bigger problem with
100 base T than I thought. Specifically, there is no defined mechanism
in the spec to autonegotiate for 100 base T cards. If I actually have
time for this, I guess I will have to find the spec and read it...
My network driver (windows) is a "NVIDIA nForce MCP Networking
Controller". It is an integrated network connector on a HP pavilion. I
do not know of a windows equivalent to lspci, so I cannot get the actual
reported hardware rev. Maybe I have to get a good live CD distro.
In this case, resetting the cable modem did not fix the problem,
although it may have fixed it in the past.
My router is a four port Linksys Router about 5 to 8 years old. My
modem is a Speedstream 5280. I am sufficiently annoyed by this problem
to consider buying a new router if this router has a force 10 base T
option for the WAN. I am willing to listen to any suggestions.
On Fri, 30 Nov 2007 16:29:17 -0500, "John Stoffel" <john(a)stoffel.org>
said:
>
> kstratton> I just went through some painful debug session(s) with my
> kstratton> ISP. For some reason, after forcing 10 base T half duplex
> kstratton> through my windows box directly to my modem (I do not
> kstratton> expect ISPs to support linux),everything suddenly worked
> kstratton> (after reconnection and re-enabling of course).
>
> Can you give more details on the cable modem box you're using and the
> PC as well? Such as what network card in the PC you are using?
>
> kstratton> How often does this kind of thing happen? I have seen this
> kstratton> kind of thing before only once before, and I was using an
> kstratton> old hub that only supported 10 base T, not a home router
> kstratton> that is supposed to autodetect the port type. I remember
> kstratton> that the modem only supports 10 base T, but I am not 100%
> kstratton> certain.
>
> Sun and Cisco were notirious for having problems figuring our
> autonegotiation on the Sun hme (Happy Meal Ethernet) cards. They'd
> end up 100Full on one side and 100 Half Duplex on the other. It would
> work, just very slowly...
>
> kstratton> Does anybody have an explanation of what most likely
> kstratton> happened? Do not hesitate to skimp on technical details or
> kstratton> references if is convenient. I desperately want to
> kstratton> understand what happened. --
>
> Something didn't autonegotiate properly. Did you try powering off
> both devices and then powering them on starting with the cable box?
>
> Also, alot of Cable Companies lock the cable box to the first MAC
> (ethernet hardware address) they see coming over the link. So if you
> boot up with a PC, and then try to move to something else like a NAT
> box or a linux box acting as a NAT box, things can go wonky.
>
> Usually a hard reset of the Cablemodem will do the trick, but
> sometimes you need to contact the ISP and ask them to reset it for
> you.
>
> In your case, it really sounds like a problem with Autonegotiation.
> Some devices just don't do a good job, esp older equipment from before
> the Gigabit ethernet stage.
>
> Just to expand on Frank's email, the people who designed the Gigiabit
> Ethernet standard over Copper (802.xxx I can't remember) saw all the
> problems with the 100/10 devices and autonegotiation and explicity
> made AutoNeg part of the spec in a very well detailed way, so that
> these problems won't happen again. As a matter of fact, Gigabit ports
> are much smarter and don't require crossover cables either, you can
> just plug them into back to back, they figure out what's going on
> automatically and adjust.
>
> The joys of big ASICs!
>
> John
> _______________________________________________
> Wlug mailing list
> Wlug(a)mail.wlug.org
> http://mail.wlug.org/mailman/listinfo/wlug
--
kstratton(a)fastmail.us
Dec. 1, 2007
Re: [Wlug] ISP/Router/Modem Ethernet communications
by John Stoffel
kstratton> I just went through some painful debug session(s) with my
kstratton> ISP. For some reason, after forcing 10 base T half duplex
kstratton> through my windows box directly to my modem (I do not
kstratton> expect ISPs to support linux),everything suddenly worked
kstratton> (after reconnection and re-enabling of course).
Can you give more details on the cable modem box you're using and the
PC as well? Such as what network card in the PC you are using?
kstratton> How often does this kind of thing happen? I have seen this
kstratton> kind of thing before only once before, and I was using an
kstratton> old hub that only supported 10 base T, not a home router
kstratton> that is supposed to autodetect the port type. I remember
kstratton> that the modem only supports 10 base T, but I am not 100%
kstratton> certain.
Sun and Cisco were notirious for having problems figuring our
autonegotiation on the Sun hme (Happy Meal Ethernet) cards. They'd
end up 100Full on one side and 100 Half Duplex on the other. It would
work, just very slowly...
kstratton> Does anybody have an explanation of what most likely
kstratton> happened? Do not hesitate to skimp on technical details or
kstratton> references if is convenient. I desperately want to
kstratton> understand what happened. --
Something didn't autonegotiate properly. Did you try powering off
both devices and then powering them on starting with the cable box?
Also, alot of Cable Companies lock the cable box to the first MAC
(ethernet hardware address) they see coming over the link. So if you
boot up with a PC, and then try to move to something else like a NAT
box or a linux box acting as a NAT box, things can go wonky.
Usually a hard reset of the Cablemodem will do the trick, but
sometimes you need to contact the ISP and ask them to reset it for
you.
In your case, it really sounds like a problem with Autonegotiation.
Some devices just don't do a good job, esp older equipment from before
the Gigabit ethernet stage.
Just to expand on Frank's email, the people who designed the Gigiabit
Ethernet standard over Copper (802.xxx I can't remember) saw all the
problems with the 100/10 devices and autonegotiation and explicity
made AutoNeg part of the spec in a very well detailed way, so that
these problems won't happen again. As a matter of fact, Gigabit ports
are much smarter and don't require crossover cables either, you can
just plug them into back to back, they figure out what's going on
automatically and adjust.
The joys of big ASICs!
John
Nov. 30, 2007
Re: [Wlug] ISP/Router/Modem Ethernet communications
by Frank Sweetser
kstratton(a)fastmail.us wrote:
> I just went through some painful debug session(s) with my ISP. For some
> reason, after forcing 10 base T half duplex through my windows box
> directly to my modem (I do not expect ISPs to support linux),everything
> suddenly worked (after reconnection and re-enabling of course).
>
> How often does this kind of thing happen? I have seen this kind of
> thing before only once before, and I was using an old hub that only
> supported 10 base T, not a home router that is supposed to autodetect
> the port type. I remember that the modem only supports 10 base T, but I
> am not 100% certain.
>
> Does anybody have an explanation of what most likely happened? Do not
> hesitate to skimp on technical details or references if is convenient.
> I desperately want to understand what happened.
Actually, that sounds like it's a problem on the PC end. Here's why.
Back when there was only 10 half, it was easy to figure out what speed and
duplex the other end was running at - 10 half!
With 100M ethernet appearing, though, you soon had dual speed cards on the
market. Rather than having to configure each and every port explicitly, users
wanted to be able to plug in and have the card just do the right thing.
Luckily, the signaling was different enough between 10 and 100 that it was
relatively straightforward for a 100M card to detect whether the other end was
speaking in 10M or 100M, and shift speeds appropriately. This is called,
simply enough, autosense.
However, speed is only half the equation. Along with 100M ethernet came
switches. Switches, by allowing for a pseudo-dedicated link per machine (as
opposed to hubs, in which the bandwidth of all links was shared by all
stations), introduced and entirely new operating mode - full duplex. Unlike
speed, there is no reliable way to passively detect what duplex the other end
is configured for. So, to solve this, and also to lay down a foundation for
interoperability as future network speeds appeared, the autonegotiation
protocol was developed. Essentially, as soon as a link is established, both
ends send a few magic packets at each other advertising what speed and duplex
combinations it supports. The two ends pick the highest performance option
supported by both, switch to that operational mode, and go on their merry way.
Even after all this, you'll still see devices appearing which only support 10
half, and don't bother to do autonegotiation. When a newer device that does
support autonegotiation is plugged into such an older device, autonegotiation
will (obviously) fail. The new end will then default to autodetection for the
speed, and will always use half duplex. This is why forcing on end of a link
to full duplex, and leaving the other end on auto, will virtually always
result in a duplex mismatch, and a link that works, just with really, really
crappy performance.
Donald Becker used to have a paper floating around describing this in a little
more detail. I can't find the original anymore, but this looks like a copy of
the same info:
http://www.negotiateddata.com/files/Bunch_Article_020095.pdf
So in the scenario you described, where the other end is sitting fixed at 10
half, it would have been up to your computer to gracefully fail
autonegotiation, and use autosense to configure the link at 10 half. Sadly,
such bugs, where chipset manufacturers assume that everyone else out there
will always support autonegotiation, are not unheard of these days.
--
Frank Sweetser fs at wpi.edu | For every problem, there is a solution that
WPI Senior Network Engineer | is simple, elegant, and wrong. - HL Mencken
GPG fingerprint = 6174 1257 129E 0D21 D8D4 E8A3 8E39 29E3 E2E8 8CEC
Nov. 30, 2007
ISP/Router/Modem Ethernet communications
by kstrattonï¼ fastmail.us
I just went through some painful debug session(s) with my ISP. For some
reason, after forcing 10 base T half duplex through my windows box
directly to my modem (I do not expect ISPs to support linux),everything
suddenly worked (after reconnection and re-enabling of course).
How often does this kind of thing happen? I have seen this kind of
thing before only once before, and I was using an old hub that only
supported 10 base T, not a home router that is supposed to autodetect
the port type. I remember that the modem only supports 10 base T, but I
am not 100% certain.
Does anybody have an explanation of what most likely happened? Do not
hesitate to skimp on technical details or references if is convenient.
I desperately want to understand what happened.
--
kstratton(a)fastmail.us
Nov. 30, 2007