Kyle Posted January 3, 2007 Posted January 3, 2007 As i have said before my server knowledge is not great and i am learning all the time. I noticed today that in a primary school ( which used to have outreach support 2 days a week, and the guy has now left) that one server which is a file server had both NICs on the server wired up. I checked ipconfig /all and sure enough they both had IP address. The on NIC had a reserved IP in DHCP and the other NIC had a manually configure IP in the same range. If you ping the server by name it replies with the manually configure IP which ends in .1, But in DHCP and all the server records the reserved IP which ends in .13 is the one that should be the one being used. Could this cause a configuration problem? I know you can configure load balancing in 2003 but having two NIC live i am not at all sure about. Can you advise me please?
john Posted January 3, 2007 Posted January 3, 2007 If its not for any form of load balancing, could be an old one thats been re-used from a proxy server job before or setup in advance for that and not used and has been accidentaly plugged in?
steve Posted January 4, 2007 Posted January 4, 2007 I initially set up my servers with 2 nics in each a couple of years ago, and they caused me no end of trouble. You need them for proxy / exchange / webserver / vpn / router. MS call it multihoming, caused me a fair few dns problems. If the adapters are the same see if you can team them, you can increase throughput / load balance and prvide a bit of redundancy.
Kyle Posted January 4, 2007 Author Posted January 4, 2007 What sort of problems did you get steve? Poor log on times, access times? How do you know it was DNS
6Foot2 Posted January 4, 2007 Posted January 4, 2007 We had similar problems a while ago: Two network cards in the same server. One had an IP manually configured and one card got an address from DHCP. We were seeing all kinds of errors: Duplicate IP addresses, stations with two IP addresses, slow network,... These issues were sorted when the cards were teamed and the manually allocated IP was used for the 'new' NIC.
tscnmuk Posted January 4, 2007 Posted January 4, 2007 We run an applications server (originally for some quite intensive science software) - it is a very high specification machine with two gigabit nic's in, each plugged into a gig port on our backbone. Since using the second nic performance has increased dramatically and sofar, touch wood, no problems whatsoever. Both of the nic's in this machines have manually assigned IP's. Could it be the IP that is assigned by DHCP that is causing the problem even though it is placed on reservation?
steve Posted January 4, 2007 Posted January 4, 2007 What sort of problems did you get steve? Poor log on times, access times? How do you know it was DNS We had browser service problems and dns issues. Found out via the error event id's generated.
john Posted January 4, 2007 Posted January 4, 2007 I would get them teamed up, have done this in a few HP servers and its very good, increased the performance a lot, so they now have a 2Gb backbone to them, seems when looking at the stats that a lot of the time it uses one port / card to send data and the other to receive it and when its high load such as at lessons start and end it then does both jobs on both so who knows what it does but it did improve stuff.
m25man Posted January 11, 2007 Posted January 11, 2007 You can use two nics connected to the same switch as they have their own IP and MAC addresses. This does not cause any problem by itself. The problems arise as the machine now has two physical interfaces to bind to it's different services. Things will fail unless you configure both the cards and the services correctly. Applications such as DNS DHCP and Wins will have a nightmare with them so if the machine is a DC god help you. If the Nics are identical (even onboard ones are often different) then there is a good chance they can be bonded with teaming software. If you want increased throughput this can be a better option. The physical interfaces are disabled by the teaming application and a third interface is created that consists of both NICs now bonded. Your switch must support this configuration, some automatically configure themselves others require link aggregation to be setup and often need cross over cables to work so do not try this while your system is needed! Save these configuration games for a holiday. Intel limit trunking to 8 adapters you can get them with 4 ports on a single PCI Nic. Read this http://en.wikipedia.org/wiki/Port_trunking and be more informed.
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now