Switch Loop with Dual NICs?

Question

If I connect two unmanaged Linksys workgroup style switches together (port to port) then I take two NIC's on a server and plug one into one switch and the other into the other switch, will this create a switching loop? I guess another way of asking it is, will a server pass broadcasts from one NIC, out the second NIC?

Thanks!

If you can possibly afford it, get some managed switches, then you could set up Spanning Tree. — Tom O'Connor, Sep 05 '13 at 20:31

GioMac · Accepted Answer · 2013-09-05T20:28:57.323

5

No it will not unless you setup bridge or forwarding on your server.

edited Sep 05 '13 at 20:28

answered Sep 05 '13 at 20:14

GioMac

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So had someone previously configured the dual nics as a bridge, I'm assuming in an attempt to team the NICs for through put, this could cause a loop? – MBFROMIT Sep 05 '13 at 20:18
Normally (one sw) teaming shouldn't do anything like this, but in this configuration teaming will cause problems because from the point of view of two switches host will run from side to side. To have redundant and working configuration you must run teaming with 802.3ad (LACP) and switches connected to the server must support stacking and update each other (like cisco xxxxS and xxxxX series of switches do). With basic round-robin balanced teaming - you must avoid connecting interfaces to two different switches. If you want teaming with generic switches - only normal way is active-passive mode. – GioMac Sep 05 '13 at 20:24

Switch Loop with Dual NICs?

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