Hello to everybody. I would like to take the advice on implementing squid with one ethernet interface and one virtual interface. Squid is configured with transparent proxy and the interfaces are working properly but the problem that can occur is that i have to run that squid for more than 100 users, that many users can result in network stuck kind of problems. If some one having experience of working on virtual interfaces with ethernet interfaces can comment on that, it would be great help. Ofcourse it is not a permanent solution if someone says that dude use another card, the cards are not expensive. but I am bound to use the one card for some days

As with any server you will have to look at the performance you are getting with your 100 users and whether your hardware is fit for the job. 100 users generating a lot of internet traffic could create a LOT of traffic, especially if it has to go in and out through the same network card. The realistic throughput of a 100Mb card is nowhere near 100Mb (closer to 60Mb) and if you are having to split this between inbound and outbound then there will be contention issues. Also check your server load levels through the use of top to see if your actual hardware is up to the task.

I don't think adding a virtual interface to the NIC is going to make that much of a difference, it may split the TCP/IP stack for some of the processing but at the end of the day it's still the same 100Mb "hole" that it's trying to push the data into.