I have a small LAN with 12 workstations.
Ever since we grew from 8 to 12 workstations last summer we've been having intermittent network problems, however the last few days the problems have gotten worse.
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Environment
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Before describing the problems, let me describe the topology...
Our router (Linksys BEFSR41 v.2) connects to the Internet via cable modem.
Connected to the router are the following...
(1) 3 Voip convertors (Linksys PAP2-CA)
(2) a 16port network switch (D-Link DSS 16 Plus) - let's call it Switch01
Connected to Switch01 are the following:
(1) 2 PCs .... Let's call them PC01 and PC02
(2) an 8port network switch (D-Link DSS-8+) - let's call it Switch02
(3) an 8port network switch (D-Link DSS-8+) - let's call it Switch03
(4) a 5port network switch (D-Link DSS-5+) - let's call it Switch04
Connected to Switch02 are the following:
(1) 2 PCs .... Let's call them PC04 and PC15
Connected to Switch03 are the following:
(1) 2 PCs .... Let's call them PC12 and PC13
Connected to Switch04 are the following:
(1) 4 PCs .... Let's call them PC03, PC14, PC18, PC21
The computers are a mixed bag of P3s -- Compaq Deskpro, Dell Latitude, IBM Netvista (all running Win2K).
The NIC cards are the originals that came with the computers.
Most of the cables are Cat5, but some are Cat5E (not that I know what that's about).
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Problems
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And now let me describe the problems...
In the morning when we turn on the computers, it usually takes about 2 hours before all the computers are recognized on the network. Some will take 15-20 minutes, while others will take about 2 hours. After that things usually go smoothly, however once in a while one of the PCs will lose it's connection to the LAN and then we have to wait a few hours till it reconnects.
Yesterday, in a desperate attempt at troubleshooting, I swapped some switches and cables. However things seemed to have gotten even worse.
Over the course of 8 hours, I visited each computer several times and took note of what computers could be seen on the network via "My Network Places". Here's what I found...
OBSERVATION 01:
On PC01, PC02, PC03, PC12, PC13
After an hour the following could be seen: PC01, PC02, PC03.
After another hour the following could be seen: PC12, PC13.
A few hours later PC14 became visable. After another hour PC21 became visable. And finally after another hour PC18 became visible.
OBSERVATION 02:
On PC14, PC18, PC21
After an hour the following could be seen: PC14, PC18, PC21
However the following could not be seen for another few hours: PC01, PC02, PC03, PC12, PC13
OBSERVATION 03:
PC04 could see only itself for the first few hours. After another hour it could see PC15. However it took several more hours until it could see the rest of the computers.
OBSERVATION 04:
PC15 could see only itself for the first few hours. Eventually it could see PC04, but that's all.
OBSERVATION 05:
After approximately 10 hours of monitoring the computers, the following happened.
PC12 lost it's connection to the LAN. For the next few hours it could not see the other computers, however it's icon could still be seen on the other computers via "My Network Places". Nevertheless if one tried to access the icon they got the following message: "network path not found".
OBSERVATION 06:
At the same time I noticed that PC15 could be seen on all the other computers (except PC12). However I am not sure if it came online before PC12 lost it's connection or afterwards.
OBSERVATION 07:
After another 2 hours PC12 could see PC12 and PC03, but could not see any other computers.
And that's where we stand now. However I suspect that after a few more hours PC12 will be able to see the rest of the computers.
OBSERVATION 08:
Another thing I noticed... It usually takes 4-5 minutes before each computer sees itself via "My Network Places". However, in some cases it has taken 10-15 minutes. This sounds like an awfully long time.
OBSERVATION 09:
Usually, if ComputerA cannot see ComputerB in "My Network Places", then ComputerA will not be able to access any of the Shares on ComputerB. However I noticed on a number of occasions that ComputerA could access ComputerB's Shares, even though it could not see ComputerB via "My Network Places".
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Questions
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Any suggestions on what's happening here?
Any suggestions on how to go about troubleshooting this mess?
Also, can you explain the curious behaviour reported above in Observations 8 and 9?
Also, regarding Observation 5 --- why did PC12s icon remain visible via "My Network Places", while it was no longer connected to the network ?
Another question, with regards to Observations 1 and 7 ...
It seems that PC03 connects more readily to the network than does it's siblings on Switch04.
I wonder why?
Another question, with regards to Observations 5 and 6
I suspect that when PC15 regained its connection to the network, it caused PC12 to lose its connection.
If that's so, do we have too many devices on the LAN? Is there some kind of limit?
Your advice is greatly appreciated.
Gary
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