Reoccurring Network Connectivity problem
Posted on 2008-06-16
For several months we have a reoccurring problem with network connectivity on some workstations. They will loose network connectivity beyond their subnet. Regardless of various troubleshoot steps it has always been found that changing to a different IP address resolves the problem. Network connectivity beyond their subnet is restored.
This has been occurring on the same subnet. The IP address is obtained automatically without trouble through DHCP. The DHCP request is forwarded by the ip helper-address command on the Cisco Catalyst switches. But the workstations are unable to contact services beyond their subnet. For example ping the gateway is successful. Printing to a network printer on the same subnet is successful. But the domain controllers and DNS which are on another subnet are unreachable. The problem is resolved by nothing more than forcing the workstation to use a different IP address. Such as configuring a static IP address outside of the DHCP range. If the workstation has a static address, configuring back to DHCP returns the original IP. Since the problem began it has rotated on some of the same workstations. Toggling between static IP and DHCP IP has been the temporary resolution until they loose network connectivity again.
The DHCP is using reservations to prevent foreign objects from easily obtain IP information.
Can anyone relate to this problem? Do any particular unusual troubleshooting steps come to mind?