The problem I am seeing, is randomly between around 3 minutes and an hour, all established network sockets are disconnected and reconnected. I typically lose the connection 2-3 times per hour. These include MSN Messenger connection, telnet connection, ssh connection etc. This happens on ethernet or wireless networks, at different locations. I've tried other laptops on the same connection which are fine.
I mentioned some of the other experimentation I have done to try and nail the problem (recommended in other threads) at the start of this thread but unfortunately none are satisfactory. I even reinstalled Windows XP which did not help.
The problem sounds very similar to that which --- from scanning the forums --- other users have experienced.
I have verified and tried multiple different network settings. The symptoms are as above.
Has there been any solution to this post? I am also having these type of problems on our fleet of Latitude C610 and C400 laptops. They all have 3Com NICS. We are on XP SP1, and randomly the network connectivity drops out and comes back. We have offline files enabled, hence the laptops are going into offline mode.
We have tried various things. Updating Nic, video drivers, etc to no avail. Does anyone know if these 3Com NICS are the cause?
I am also waiting patiently for a solution to this problem. It seems there are many people with the same connection dropping problem.
What wireless card and router are you using neilacarson? I'm using the Truemobile 1300 MiniPCI and the TM 2300 router. I have had the router replaced with a new one and it still has not solved the problem. I am having a Dell rep come over today to change the TM1300 wireless card, but I suspecting that this too will not solve the problem as others have mentioned doing this without success.
As has been mentioned, I have also tried many different solutions given by Dell tech support and whatever I found on this and other boards. But I can't seem to keep a connection for long periods of time. It is random but anywhere from 5 mins -1 hour. I was on the phone with tech support and watched the connection come up and down 3 times while I didn't even touch the laptop. (latest hardware drivers and OS updates have been installed and both the 1300 and 2300 operate on channel 11 (other channels have been tested too))
The next attempt will be to reformat the entire system and start from scratch again (this is what Dell tech support said would need to be done in order to get to the next stage, which is getting my money back and buying LinkSys gear ;) ). Unless the laptop came installed with bogus drivers that can't be uninstalled, then I'm not sure how this will help. I have only had the system for 4 months and it has never worked consistently, even with default configurations.
Somebody Please find a solution :) and ideas BobT?
This sounds like a speed / duplex negotiation problem. I see this quite often with the 3COM cards in particular.
There is something about the tranceiver in the 3Com 3C9xx series (and a few others that are related chipsets) where the drivers don't always perform the auto-negotiation correctly (if you have a monitor tool you may see the interface switching between 10 and 100 Mbs - the duplex remains at full for both). In Linux you have to force the full_duplex mode with the VORTEX driver kernel option - in windows, if you have the older driver (like in windows 2000), there is an option that says "hardware default" - and that is telling the tranceiver on the card to use the current saved hardware default setting (which is usually 100/full). I have yet to figure out if this is a problem with the switch / NIC combination, or just a 3com problem in general. Whatever the problem - they don't seem to do N-way very well whatever the cause...
to see if this is your problem - manually set the card for 100/full from "auto detect". Problem should persist. Set the card for 10/full (Assuming you have a switch not a hub). Does the problem go away? (after changing the settings, disable then re-enable the card to make sure the changes take effect).
This is fine for people who only access the internet, because their connections are slower than 10mbps - but on a LAN (like at work) it is annoying. Switching drivers may help - although I have gotten tired of messing with it to the point where I think I am going to swap to intel based network adapters (the windows drivers seem to like those better).
If you have a laptop, like the C610 I have - you don't have a choice in adapters, unless you go with an external PCMCIA type.
NOTE: one faulty driver on one card can cause other computers attached to the same switch to experience the problem... so if you have a faulty network cable or driver that causes it with one host, the others may see similar problems as the switch tries to deal with it (assuming it is a small "dumb" switch - unmanaged, layer two only).
My problem went away when I switched one computer back to 10/full from 100/full (All computers attached were experiencing network slowness, but one was showing the connect / disconnect thing).
So, in my case, it's either:
bad cable
bad driver
bad port in switch
bad port in computer
And this problem affected all the machines attached to the switch - they were all slow to the internet (As the switch tries to deal with the bad connection and the constant re-negotiation) - but only the offending ones showed the link up/down in windows. Linux will show you more detailed errors in the /var/log/messages file - evidently the linux driver has the same problem with the n-way negotiation as well (this is documented on several linux sites).
The strangest thing is - some days it won't affect anything at all, then other days it's every few minutes.
Also, just for the sake of formality - my problems were also irrespective of network hub, switch, ethernet mode, use or non-use of crossover cables, etc. I twiddled all of these too.
So, I can explain all my experiences and what I came up with. Apologies if this is a long thread. Hopefully my response can benefit some of you guys.
So, I went through a long process getting my TrueMobile 1300 (in D800) to talk to something. My old Lucent Orinoco gateway talked to it fine at 802.11b, but unfortunately I was dieing and had to replace it with something - hence this message.
The first thing I tried to replace it with was a LinkSys gateway, 802.11b and 802.11g. I can't remember the model, since I returned it. Before upgrading my Dell drivers to the latest version, the laptop would not detect the AP. After upgrading, although the laptop would detect and work with the gateway fine, I found that the "connection drop" was due to large packet loss. For small-sized packets, 'pinging' the router was completely reliable, but when pinging with large-sized packets, eg ping -l 1500 for 1500-byte packets, large quantities were getting lost. Typically, when packet loss becomes more than a small (very small number) of percent, connections can start 'dropping' or at least pausing/timing out. This occured in both 802.11b _and_ 802.11g mode.
After returning this, I purchased a D-Link PCI card with the goal of using this inside my other PC (also running Windows XP) and turning that PC into the base station using 'ad-hoc' mode. This worked 100% reliably in 802.11b mode, just like the old Lucent gateway - no packet loss, even for large packets. The problem with this was that 802.11g mode did not work, and upon calling D-Link tech support, they told me that 802.11g mode is deliberately only enabled when using other D-Link devices due to the (in)compatibility issues they had been experiencing. The other problem was that, since this was a PCI card that went on the back of a PC, the PC case itself was physically between my laptop and the antenna, meaning reception range was not sufficiently high. So, I returned this due to the lack of 'g' interoperability and range.
Then, at a crossroads between just running ethernet through the ceiling and trying once more, I purchased the Microsoft-labelled access point since it was certified compatible with most wi-fi standards it supported. Upon firing it up, I noticed similar packet loss problems to the Linksys AP, in both b and g mode, though not as strongly pronounced. Running out of ideas, I tried changing the channels on the AP. Miraculously, I found that the lower the channel number, the lower the packet loss, until I set the AP to the lowest possible channel at which point I experienced zero packet loss, even for huge packets. Bingo, but very odd. Notice all of this is regardless of encryption mode or other settings. When I increase the channel number even now, packet loss reliably returns.
So I've been at least able to find a combination that works, by sticking to the low channel numbers. Who knows, maybe the LinkSys AP would have been fine too on low channels. Maybe some interference in my area, or ??? Hard to explain, since a number of the channels overlap anyway. But the system has been 100% reliable since this change, anyhow.
Interestingly, I recently visited my neighbour to help him with some wireless problems, and his combination (Linksys AP, Cisco PCMCIA card inside IBM laptop) was showign similar packet loss issues. I lowered the channel number, and they went away too. Really, most odd.
So in summary, I'm not sure this will help anyone, but I did find a working combo - Microsoft AP with Truemobile 1300 on low channel number. If I had to do this again, though, I would probably just run ethernet through the walls/ceiling before moving in...
neilacarson
4 Posts
0
June 6th, 2003 21:00
Thank you for your response Bob.
The problem I am seeing, is randomly between around 3 minutes and an hour, all established network sockets are disconnected and reconnected. I typically lose the connection 2-3 times per hour. These include MSN Messenger connection, telnet connection, ssh connection etc. This happens on ethernet or wireless networks, at different locations. I've tried other laptops on the same connection which are fine.
I mentioned some of the other experimentation I have done to try and nail the problem (recommended in other threads) at the start of this thread but unfortunately none are satisfactory. I even reinstalled Windows XP which did not help.
The problem sounds very similar to that which --- from scanning the forums --- other users have experienced.
I have verified and tried multiple different network settings. The symptoms are as above.
Thank you.
kory
12 Posts
0
December 9th, 2003 11:00
Hi
Has there been any solution to this post? I am also having these type of problems on our fleet of Latitude C610 and C400 laptops. They all have 3Com NICS. We are on XP SP1, and randomly the network connectivity drops out and comes back. We have offline files enabled, hence the laptops are going into offline mode.
We have tried various things. Updating Nic, video drivers, etc to no avail. Does anyone know if these 3Com NICS are the cause?
Dave
Mako
14 Posts
0
December 17th, 2003 15:00
I am also waiting patiently for a solution to this problem. It seems there are many people with the same connection dropping problem.
What wireless card and router are you using neilacarson? I'm using the Truemobile 1300 MiniPCI and the TM 2300 router. I have had the router replaced with a new one and it still has not solved the problem. I am having a Dell rep come over today to change the TM1300 wireless card, but I suspecting that this too will not solve the problem as others have mentioned doing this without success.
As has been mentioned, I have also tried many different solutions given by Dell tech support and whatever I found on this and other boards. But I can't seem to keep a connection for long periods of time. It is random but anywhere from 5 mins -1 hour. I was on the phone with tech support and watched the connection come up and down 3 times while I didn't even touch the laptop. (latest hardware drivers and OS updates have been installed and both the 1300 and 2300 operate on channel 11 (other channels have been tested too))
The next attempt will be to reformat the entire system and start from scratch again (this is what Dell tech support said would need to be done in order to get to the next stage, which is getting my money back and buying LinkSys gear ;) ). Unless the laptop came installed with bogus drivers that can't be uninstalled, then I'm not sure how this will help. I have only had the system for 4 months and it has never worked consistently, even with default configurations.
Somebody Please find a solution :) and ideas BobT?
Cheers
Message Edited by Mako on 12-17-2003 11:21 AM
schnabba
1 Message
0
December 27th, 2003 16:00
This sounds like a speed / duplex negotiation problem. I see this quite often with the 3COM cards in particular.
There is something about the tranceiver in the 3Com 3C9xx series (and a few others that are related chipsets) where the drivers don't always perform the auto-negotiation correctly (if you have a monitor tool you may see the interface switching between 10 and 100 Mbs - the duplex remains at full for both). In Linux you have to force the full_duplex mode with the VORTEX driver kernel option - in windows, if you have the older driver (like in windows 2000), there is an option that says "hardware default" - and that is telling the tranceiver on the card to use the current saved hardware default setting (which is usually 100/full). I have yet to figure out if this is a problem with the switch / NIC combination, or just a 3com problem in general. Whatever the problem - they don't seem to do N-way very well whatever the cause...
to see if this is your problem - manually set the card for 100/full from "auto detect". Problem should persist. Set the card for 10/full (Assuming you have a switch not a hub). Does the problem go away? (after changing the settings, disable then re-enable the card to make sure the changes take effect).
This is fine for people who only access the internet, because their connections are slower than 10mbps - but on a LAN (like at work) it is annoying. Switching drivers may help - although I have gotten tired of messing with it to the point where I think I am going to swap to intel based network adapters (the windows drivers seem to like those better).
If you have a laptop, like the C610 I have - you don't have a choice in adapters, unless you go with an external PCMCIA type.
NOTE: one faulty driver on one card can cause other computers attached to the same switch to experience the problem... so if you have a faulty network cable or driver that causes it with one host, the others may see similar problems as the switch tries to deal with it (assuming it is a small "dumb" switch - unmanaged, layer two only).
My problem went away when I switched one computer back to 10/full from 100/full (All computers attached were experiencing network slowness, but one was showing the connect / disconnect thing).
So, in my case, it's either:
And this problem affected all the machines attached to the switch - they were all slow to the internet (As the switch tries to deal with the bad connection and the constant re-negotiation) - but only the offending ones showed the link up/down in windows. Linux will show you more detailed errors in the /var/log/messages file - evidently the linux driver has the same problem with the n-way negotiation as well (this is documented on several linux sites).
The strangest thing is - some days it won't affect anything at all, then other days it's every few minutes.
hope this helps narrow down the problem.
neilacarson
4 Posts
0
December 28th, 2003 18:00
Also, just for the sake of formality - my problems were also irrespective of network hub, switch, ethernet mode, use or non-use of crossover cables, etc. I twiddled all of these too.
neilacarson
4 Posts
0
December 28th, 2003 18:00
So, I can explain all my experiences and what I came up with. Apologies if this is a long thread. Hopefully my response can benefit some of you guys.
So, I went through a long process getting my TrueMobile 1300 (in D800) to talk to something. My old Lucent Orinoco gateway talked to it fine at 802.11b, but unfortunately I was dieing and had to replace it with something - hence this message.
The first thing I tried to replace it with was a LinkSys gateway, 802.11b and 802.11g. I can't remember the model, since I returned it. Before upgrading my Dell drivers to the latest version, the laptop would not detect the AP. After upgrading, although the laptop would detect and work with the gateway fine, I found that the "connection drop" was due to large packet loss. For small-sized packets, 'pinging' the router was completely reliable, but when pinging with large-sized packets, eg ping -l 1500 for 1500-byte packets, large quantities were getting lost. Typically, when packet loss becomes more than a small (very small number) of percent, connections can start 'dropping' or at least pausing/timing out. This occured in both 802.11b _and_ 802.11g mode.
After returning this, I purchased a D-Link PCI card with the goal of using this inside my other PC (also running Windows XP) and turning that PC into the base station using 'ad-hoc' mode. This worked 100% reliably in 802.11b mode, just like the old Lucent gateway - no packet loss, even for large packets. The problem with this was that 802.11g mode did not work, and upon calling D-Link tech support, they told me that 802.11g mode is deliberately only enabled when using other D-Link devices due to the (in)compatibility issues they had been experiencing. The other problem was that, since this was a PCI card that went on the back of a PC, the PC case itself was physically between my laptop and the antenna, meaning reception range was not sufficiently high. So, I returned this due to the lack of 'g' interoperability and range.
Then, at a crossroads between just running ethernet through the ceiling and trying once more, I purchased the Microsoft-labelled access point since it was certified compatible with most wi-fi standards it supported. Upon firing it up, I noticed similar packet loss problems to the Linksys AP, in both b and g mode, though not as strongly pronounced. Running out of ideas, I tried changing the channels on the AP. Miraculously, I found that the lower the channel number, the lower the packet loss, until I set the AP to the lowest possible channel at which point I experienced zero packet loss, even for huge packets. Bingo, but very odd. Notice all of this is regardless of encryption mode or other settings. When I increase the channel number even now, packet loss reliably returns.
So I've been at least able to find a combination that works, by sticking to the low channel numbers. Who knows, maybe the LinkSys AP would have been fine too on low channels. Maybe some interference in my area, or ??? Hard to explain, since a number of the channels overlap anyway. But the system has been 100% reliable since this change, anyhow.
Interestingly, I recently visited my neighbour to help him with some wireless problems, and his combination (Linksys AP, Cisco PCMCIA card inside IBM laptop) was showign similar packet loss issues. I lowered the channel number, and they went away too. Really, most odd.
So in summary, I'm not sure this will help anyone, but I did find a working combo - Microsoft AP with Truemobile 1300 on low channel number. If I had to do this again, though, I would probably just run ethernet through the walls/ceiling before moving in...
Regards,
Neil