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I would like to add a second loopback network device on Linux, so that I have lo and (e.g.) lo2. This is so that I can use netem to simulate a throttled network over lo2 without compromising my standard loopback interface.

Note that I can not use an alias interface here (such as lo:1) since netem will affect the underlying (lo) interface, not the interface alias.

How can that be done?

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up vote 1 down vote accepted

Can you add a virtual tap device and do the testing on that?

ip tuntap add dev tap0 mode tap

You may need to install/insmod the tun driver first.

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Thanks. That sounds like it should work. – Paul Cager Feb 21 '13 at 12:57

Can't do. The net is always loopback ( is just conventional). This is enforced by the kernel.

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