November 2007 - WLUG - wlug.mailman3.com

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 kstratton＠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

Solaris automounter

by vze284qe＠verizon.net

Hi All, At work I have a SunFire v245 (Sparc) running SunOs 5.10, which I guess is Solaris 10. When I put a CD in the drive, it doesn't get mounted. I checked to see if 'vold' was running and it was. What else should I check for? I'm not too familiar with Solaris, so any help is appreciated. TIA, -Chuck

Nov. 29, 2007

Any XMl-types out there?

by Stephen Daukas

Hello Everyone! So, I have to teach myself myself XML, XSL, et al., for work... (The VB stuff is in the background for now!) I started playing with XML yesterday, and have gotten pretty far along. But... I have to deal with M$-generated XML files that looks like the following (I added the first two lines for display in a browser): <?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="SOURCES.xsl"?> <xml xmlns:s='uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882' xmlns:dt='uuid:C2F41010-65B3-11d1-A29F-00AA00C14882' xmlns:rs='urn:schemas-microsoft-com:rowset' xmlns:z='#RowsetSchema'> <s:Schema id='RowsetSchema'> <s:ElementType name='row' content='eltOnly'> <s:AttributeType name='ID305B' rs:number='1' rs:nullable='true' rs:maydefer='true' rs:writeunknown='true'> <s:datatype dt:type='string' dt:maxLength='50'/> </s:AttributeType> [snip] <s:extends type='rs:rowbase'/> </s:ElementType> </s:Schema> <rs:data> <z:row ID305B='MA11002' CYCLE='2002' USE_ID='537' CAUSE_ID='226' SOURCE_ID='180' CONFIRMED='N'/> [~11,000 lines snipped] So, I wrote the following SOURCES.xsl file to display this beast in a browser (it uses recursion): <?xml version='1.0'?> <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:rs='urn:schemas-microsoft-com:rowset' xmlns:z='#RowsetSchema' version="1.0"> <xsl:template match="/"> <HTML> <BODY topmargin="0" leftmargin="0"> <xsl:apply-templates select="/xml/rs:data"/> </BODY> </HTML> </xsl:template> <xsl:key name="rows-by-AU" match="z:row" use="@ID305B" /> <xsl:template match="z:row"> <xsl:apply-templates select="key('rows-by-AU', ID305B)" /> <div AU_ID="{ID305B}"> <xsl:apply-templates select="key('rows-by-AU', ID305B)" /> <div USE_ID="{CYCLE}"> <div USE_ID="{USE_ID}"> <xsl:value-of select="@ID305B"/> (<xsl:value-of select="@CYCLE"/>): <xsl:apply-templates select="key('rows-by-AU', USE_ID)"/> <xsl:value-of select="@USE_ID"/> - <xsl:value-of select="@CAUSE_ID"/> - <xsl:value-of select="@SOURCE_ID"/> </div> </div> </div> </xsl:template> </xsl:stylesheet> And it works (surprised the hell out of me)! But now I'm having the hardest time figuring out how to format this the way I'd like. This is how it currently looks in the browser: MA11002 (2002): 537 - 226 - 180 MA11002 (2002): 537 - 448 - 140 MA11002 (2002): 538 - 226 - 180 MA11002 (2002): 538 - 413 - 140 MA11002 (2002): 538 - 413 - 177 MA11002 (2002): 539 - 226 - 180 MA11002 (2002): 539 - 413 - 140 MA11002 (2002): 541 - 226 - 180 MA11002 (2002): 541 - 478 - 140 MA11002 (2002): 541 - 413 - 140 MA11018 (2002): 538 - 413 - 140 MA11018 (2002): 539 - 413 - 140 MA11018 (2002): 541 - 413 - 140 MA11019 (2002): 537 - 312 - 140 MA11019 (2002): 538 - 312 - 140 MA11019 (2002): 539 - 312 - 140 MA11019 (2002): 541 - 312 - 140 [... other IDs in between 2002 and 2008 ...] MA11002 (2008): 537 - 226 - 180 MA11002 (2008): 537 - 478 - 92 MA11002 (2008): 537 - 312 - 156 [... thousands of additional IDs ...] And I'd like the output to look something like: MA11002 (2002): 537 - 226 - 180 - 448 - 140 538 - 226 - 180 - 413 - 140 - 177 539 - 226 - 180 - 413 - 140 MA11002 (2008): 537 - 226 - 180 - 478 - 92 - 312 - 156 [...] So, things would need to be grouped by ID305B and CYCLE, then by USE_ID, then by CAUSE_ID, then by SOURCE_ID. But, I'd even settle for output that looks like: MA11002 (2002): 537 - 226 - 180 MA11002 (2002): 537 - 448 - 140 MA11002 (2002): 538 - 226 - 180 MA11002 (2002): 538 - 413 - 140 MA11002 (2002): 538 - 413 - 177 MA11002 (2002): 539 - 226 - 180 MA11002 (2002): 539 - 413 - 140 MA11002 (2002): 541 - 226 - 180 MA11002 (2002): 541 - 478 - 140 MA11002 (2002): 541 - 413 - 140 MA11002 (2008): 537 - 226 - 180 MA11002 (2008): 537 - 478 - 92 MA11002 (2008): 537 - 312 - 156 [... thousands of additional IDs ...] where the IDs from the two different years are adjacent to one another... I believe this will involve much pain and suffering while I try to figure out such things as XML nodes, grouping, sorting, and the like... But, I'm hoping someone will look at this and say "boy Daukas, that's easy... just do this, and then that, and voila - your done!". Anyone? Anyone? ;-) Thanks in advance for any help! Steve

Nov. 28, 2007

Re: [Wlug] Information for Linux newbies?

by Eric Martin

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Kevin Harrington wrote: > As i mentioned at the meeting this past week I am going to be > giving a seminar for linux newbies and would like to pull from > people that know better then i do on what i should teach people. > What i would like to know is: What are some things that you wish > you had known as a newbie? Think back to your very first linux > install and any short-cuts, tips, tricks, and gatcha's that would > make peoples first experience easier. There is a lot of windows > resentment after the slow trainwreck that is vista, so lets see if > we can get a few new converts! My biggest thing would be to explain to people (at all levels) how to do what they are currently doing. Firefox for browsing, OO.o for Office stuff, gimp for photoshop, etc. I also agree with Tim in pitching to your audience, and Andy has a great point with making sure stuff works via LiveCDs. When I was a newbie I just wanted to read books on all the stuff. If you have some people like that, I'd point them to their distro docs / google. HTH Eric -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHSPXDaiVxdKlBO58RAp4RAJ9l/162tA/6wqSYrRMx+kbdCh9ipACfYrM8 3gkLyp8yT/viUpXknRVdgy8= =PshY -----END PGP SIGNATURE-----

Nov. 25, 2007

Re: [Wlug] Xinerama issues with Fedora Core 8...

by Tim Keller

Hey that fixed it! Thanks! Tim. On 11/20/07, Chuck Anderson <cra(a)wpi.edu> wrote: > On Tue, Nov 20, 2007 at 10:26:24AM -0500, Tim Keller wrote: > > Section "Device" > > Identifier "Videocard0" > > Driver "radeon" > > Option "Monitor-VGA-0" > > Option "Monitor-DVI-0" > > BusID "PCI:1:9:0" > > EndSection > > You forgot the second argument to the Montior- options here. > > Section "Device" > Identifier "Videocard0" > Driver "radeon" > Option "Monitor-VGA-0" "first" > Option "Monitor-DVI-0" "second" > BusID "PCI:1:9:0" > EndSection > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > -- I am leary of the allegiances of any politician who refers to their constituents as "consumers".

Nov. 21, 2007

initrd.img file

by vze284qe＠verizon.net

Hello, I built a custom "gutsy gibbon" kernel, but I can't find the corresponding initrd.img file. There's a link in / that looks like this: initrd.img-> boot/initrd.img-2.6.22-generic. Shouldn't there be a new initrd.img file that was created when I built the new kernel or am I missing something? TIA, -- -Chuck

Nov. 20, 2007

Re: [Wlug] Xinerama issues with Fedora Core 8...

by Chuck Anderson

On Tue, Nov 20, 2007 at 10:26:24AM -0500, Tim Keller wrote: > Section "Device" > Identifier "Videocard0" > Driver "radeon" > Option "Monitor-VGA-0" > Option "Monitor-DVI-0" > BusID "PCI:1:9:0" > EndSection You forgot the second argument to the Montior- options here. Section "Device" Identifier "Videocard0" Driver "radeon" Option "Monitor-VGA-0" "first" Option "Monitor-DVI-0" "second" BusID "PCI:1:9:0" EndSection

Nov. 20, 2007

Re: [Wlug] Xinerama issues with Fedora Core 8...

by Tim Keller

Actually, I found *another* radeon card that has two inputs and I followed your instructions and now I have cloned monitors... so I'm going in the right direction... How do I unclone them? Thanks, Tim. BTW... here is my xorg.conf file for reference... # Xorg configuration created by system-config-display Section "ServerLayout" Identifier "Duel head single card setup" Screen 0 "Screen0" 0 0 InputDevice "Keyboard0" "CoreKeyboard" EndSection Section "InputDevice" Identifier "Keyboard0" Driver "kbd" Option "XkbModel" "pc105" Option "XkbLayout" "us+inet" EndSection Section "Device" Identifier "Videocard0" Driver "radeon" Option "Monitor-VGA-0" Option "Monitor-DVI-0" BusID "PCI:1:9:0" EndSection Section "Monitor" Identifier "first" EndSection Section "Monitor" Identifier "second" Option "RightOf" "first" EndSection Section "Screen" Identifier "Screen0" Device "Videocard0" Monitor "first" DefaultDepth 24 SubSection "Display" Viewport 0 0 Virtual 2560 1024 Depth 24 EndSubSection EndSection On Nov 19, 2007 4:06 PM, Chuck Anderson <cra(a)wpi.edu> wrote: > On Mon, Nov 19, 2007 at 03:25:19PM -0500, Tim Keller wrote: > > So... if I'm reading this right... I'm stuck then... since I have > monitors > > on separate video cards. > > > > I know it's cool that xrandr can do all this funky stuff, but I'd just > be > > happy to keep existing functionality. > > > > What are my options now... downgrade my X server? > > I guess so... good luck getting an older Xorg to run on Fedora 8. > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > -- I am leary of the allegiances of any politician who refers to their constituents as "consumers".

Nov. 20, 2007