Re: Duplex setting
The list has been flaky today, so you may have received some replies that I didn't see yet. I don't know of any specific references regarding this, but autonegotiation is VERY flaky and should be avoided like the plague, even if it seems to work most of the time. If you use it, I promise you it will come back to bite you. It looks like you've already discovered this. The problem seems to be that vendors have just slightly different implementations of it and it's not a very specific process. Inevitably, one end of the link chooses a different speed/duplex setting than the other side, and you never know when it's going to happen. Things might be humming along for months without a problem, then one day...boom...your users can't reach your server, or whatever. You troubleshoot for half an hour and can find no reason for the problem. Then, when you reboot, maybe it starts working again so you ignore it until the next time it happens, never suspecting the actual culprit was autonegotiation. Always hard-set your speed and duplex settings. Manual settings good, autonegotiation very bad! Oh, I should mention one time that it was a good thing, but not in the expected way. We had a Nortel Meridian PBX with an ethernet card in it. We were having problems and it turned out that the PBX software was reporting one speed/duplex setting while actually using another. We discovered this by turning on autonegotiate temporarily on the ethernet switch. Once we saw what was happening, we fixed the PBX software and then hardset the switch back to what we wanted. HTH, John > I've read in messages, and in books, about setting the duplex to full/half > vs. auto. I knew that it was flaky, but no specifics. We had a machine > losing connectivity, and it turns out this was the reason. I changed the > port from auto to full duplex, and everything seems to work great. Is there > any specific information as to what can cause this? For instance, maybe the > auto-detect detects it as half then changes to full, causing a brief outage > in connectivity? > > > Thanks, > Joey Fowler > > We are told that talent creates its own opportunities. But it sometimes > seems that intense desire creates not only its own opportunities, but its > own talents. > - Eric Hoffer (1902-1983 American Author & Philosopher) > > > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] ___ Send a cool gift with your E-Card http://www.bluemountain.com/giftcenter/ _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Duplex setting
:) Nope it is not a $15 noname NIC. It is a Compaq NC3131 FastEthernet NIC. I don't know the exact price put I'm guessing 10-20 times that amount. The link that was given to me by someone else in this group, showed that Cisco says all Routers, Servers and production equipment should have this set manually, and that the auto setting should be used for Migrant users. -Original Message- From: Hornbeck, Timothy [mailto:[EMAIL PROTECTED]] Sent: Monday, February 05, 2001 1:14 PM To: '[EMAIL PROTECTED]' Subject: RE: Duplex setting In the past, everyone would blame the switch. If it was the switch then every NIC or device would have this problem. I have found that it's usually the NIC driver causing the issue. Is the NIC a reputable manufacture or is it a $15 noname NIC? This might also be the issue. Check to see if you can find a new driver. This will probably solve your problem. In the meantime you should be fine with setting the port to Full/Half duplex. - Tim -Original Message- From: Fowler, Robert J. [mailto:[EMAIL PROTECTED]] Sent: Monday, February 05, 2001 12:34 PM To: [EMAIL PROTECTED] Subject: Duplex setting I've read in messages, and in books, about setting the duplex to full/half vs. auto. I knew that it was flaky, but no specifics. We had a machine losing connectivity, and it turns out this was the reason. I changed the port from auto to full duplex, and everything seems to work great. Is there any specific information as to what can cause this? For instance, maybe the auto-detect detects it as half then changes to full, causing a brief outage in connectivity? Thanks, Joey Fowler We are told that talent creates its own opportunities. But it sometimes seems that intense desire creates not only its own opportunities, but its own talents. - Eric Hoffer (1902-1983 American Author & Philosopher) _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Duplex setting
This sounds a little like that "If your wife ran on IOS" thread from a couple months ago... ;-) - Original Message - From: Howard C. Berkowitz To: [EMAIL PROTECTED] Sent: Monday, February 05, 2001 2:08 PM Subject: RE: Duplex setting One duplex setting is from Mars and the other is from Venus. Autonegotiation works only when the negotiator understands which is from where, and how to speak the language of each. ;-) _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Duplex setting
One duplex setting is from Mars and the other is from Venus. Autonegotiation works only when the negotiator understands which is from where, and how to speak the language of each. ;-) _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Duplex setting
Robert, This is true. I have recently done some tweaks on our new Cisco 4006's which we have installed in the network closets. Included in the items I researched were: Enabling portfast on ports connected to servers and workstations. Disabling Etherchannel and trunking (which I found out, are set to autonegotiate by default on Cisco Switches). And also, hardsetting the port switches to match the capabilities of the NIC cards. I had to do this for most of my Linux/Unix users as they were seeing the errors more than my PC users. Here are some links to some information from the Cisco website that I came across while doing my research: http://www.cisco.com/warp/public/473/3.html http://www.cisco.com/warp/public/473/46.html Hope this information helps! Heather Buri -Original Message- From: Fowler, Robert J. [mailto:[EMAIL PROTECTED]] Sent: Monday, February 05, 2001 11:34 AM To: [EMAIL PROTECTED] Subject: Duplex setting I've read in messages, and in books, about setting the duplex to full/half vs. auto. I knew that it was flaky, but no specifics. We had a machine losing connectivity, and it turns out this was the reason. I changed the port from auto to full duplex, and everything seems to work great. Is there any specific information as to what can cause this? For instance, maybe the auto-detect detects it as half then changes to full, causing a brief outage in connectivity? Thanks, Joey Fowler We are told that talent creates its own opportunities. But it sometimes seems that intense desire creates not only its own opportunities, but its own talents. - Eric Hoffer (1902-1983 American Author & Philosopher) _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Duplex setting
In the past, everyone would blame the switch. If it was the switch then every NIC or device would have this problem. I have found that it's usually the NIC driver causing the issue. Is the NIC a reputable manufacture or is it a $15 noname NIC? This might also be the issue. Check to see if you can find a new driver. This will probably solve your problem. In the meantime you should be fine with setting the port to Full/Half duplex. - Tim -Original Message- From: Fowler, Robert J. [mailto:[EMAIL PROTECTED]] Sent: Monday, February 05, 2001 12:34 PM To: [EMAIL PROTECTED] Subject: Duplex setting I've read in messages, and in books, about setting the duplex to full/half vs. auto. I knew that it was flaky, but no specifics. We had a machine losing connectivity, and it turns out this was the reason. I changed the port from auto to full duplex, and everything seems to work great. Is there any specific information as to what can cause this? For instance, maybe the auto-detect detects it as half then changes to full, causing a brief outage in connectivity? Thanks, Joey Fowler We are told that talent creates its own opportunities. But it sometimes seems that intense desire creates not only its own opportunities, but its own talents. - Eric Hoffer (1902-1983 American Author & Philosopher) _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
