We have been experiencing for almost a week a very frustrating problem of 2 NT4 BDCs, one an Exchange Server, that intermittently time out talking to each other and the W98 stations on the net. We have tried everything to isolate the problem and nothing works longer than about 45 minutes.
Chronology:
Power cycled on all equipment once while testing electrical circuits.
Closet with Cayman router, Cisco PIX506, Cisco 2950 and 2924 switches may/may not have been cycled without the benefit of UPS.
4 NT Servers: jf1 PDC, Exchange and EB2 BDC all on GEB domain; EB on JFEDEB domain used only as RAS. All shut down and restarted in sequence.
New APC 2200 UPS with splitter card replaced old 1400 on JF1, EB2 and EB attached as simple connect. PowerChute 5.2 loaded on EB2.
Symptoms:
EB2 and/or Exchange stop talking to each other and workstations. Sometime a one way ping works. After anywhere between 5 and 45 minutes connections fail. After some time, connections reestablished.
Trend IISand Office on EB2 monitoring and deploying ServerProtect on all servers.
We have examined, cycled, reset Ciscos, arp, cross connected 2 servers and still had problem. Replaced a nic on one of the 2 Dell 2500 servers with no success.
All engineers are stumped. Dell says not a hardware issue. Microsoft denies software.
All suggestions appreciated.