For those of you that have ever setup a server with two NICs, you probably know that it’s usually best to either a) team the NICs to have greater performance, or b) have them on completely separate LANs and only have one that is registered in DNS with the domain name that you are hosting out your site through.A few weeks ago, while working on a dev lab MOSS Server in a medium farm configuration I ran into a problem where the server in question was configured with the same gateway on both NICs, but the NICs were in completely separate subnets, thereby causing some traffic to drop as the NIC attempting to pass traffic to a gateway which was not situated on the subnet for which the NIC was configured for. Needless to say after scratching my head for a while and wondering why 500 error messages were coming up sporadically and after checking the supporting AD infrastructure it was back to the basics of checking network connections. Fortunately after about five minutes of reviewing adapter configurations the issue was remedied by removing the DNS registration of the secondary NIC (used for backups and remote desktop administration) in addition to removing the gateway so that all traffic requests would be responding through the primary NIC.
Level of difficulty in resolving the issue – pretty low, however definitely recommend some basic networking courses to all the aspiring SharePoint Infrastructure Engineers out there so that they’re able to troubleshoot their surrounding network for issues which may affect their system.
The Tech Blog of Dan Usher 