Re: Two NICs in one machine and same LAN?

From: Kevin D. Goodknecht Sr. [MVP] (admin_at_nospam.WFTX.US)
Date: 07/06/04 

Date: Tue, 6 Jul 2004 16:26:55 -0500

In news:uGiowr5YEHA.2480@tk2msftngp13.phx.gbl,
RQ <r.qian@inetmail.att.net> posted a question
Then Kevin replied below:
> Would you please provide a answer why it's not a good
> idea?
Because they are different networks, and should be addressed acordingly.
Lets say that there is a machine with IP 10.1.1.3, which network provides
the way to that machine?
 If one is 10.1.1.x and the other is also 10.1.1.x the machine won't know
which way to go to get to a machine that is on one or the other networks.
One should be 10.1.1.x and the other could be 10.1.0.x.
If both NICs are on the same subnet, they should be teamed and would only
have one IP address for both NICs. If you have two NICs on the same machine
with different IP addresses looking at each other (not teamed) only one will
get used at a time. Plus, if you have NetBIOS enabled, one of the NICs if
not both will be disabled due to a NetBIOS name conflict. It is like having
to machines on the same Network with the same NetBIOS name.

Suppose a query is sent to DNS for this machine and DNS gives the 10.1.1.1
address but that address is not on the subnet that has that address?
Ther is no way for DNS to know which address to give, it will just use round
robin. If they are on different subnets, DNS will use Netmask ordering to
give the correct record. (based on 10.1.1.x or 10.1.0.x) 

-- 
Best regards,
Kevin D4 Dad Goodknecht Sr. [MVP]
Hope This Helps
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