One Expansion Chassis, Multiple NCP Systems!

[mohamed.sabbah]

Dear!

Assume I have one expansion chassis V3000, loaded with two E1 modules/cards. I want to assign each E1 module to different NBX NCP (3001R). My plan is not connect the chassis Ethernet port to the network, but rather I will connect the Ethernet ports on the E1 cards themsleves, where each card will connect to different VLAN corresponding to its NBX. Here I am trying to isolate the two NBX NCP from each other for not to have conflicts, but still I want to share the chassis!

Will this work?

[merlin_1]

In the past , 2 NBX'es on the same network will commonly cause issues of discovery . However, Setting up 2 vlans , The NBX's would have to have access to both vlans . I have not done this in the past but I would think You could set it up . I would be careful of the ports the NBX's are plugged into as the tels need only to have the VLan they reside on and set up in the NBX for this VLan . What we have dealt with here is that when an NBX device boots up for the first time , A tel will see both NCP's and display pick an NBoss . A digital Line card will arp out and the first NCP that answers , will attach to . So we suggest to temporarily remove the NBX that you do not want to attach to then discover your components , then plug the NCP back in after discovery and vice Versa after the 2nd NCP components are discovered . It is not recommended but it will work . Once the devices are discovered they will only arp out at Layer 2 for the NCP that it was attached to thus eliminating arping out for a new NCP . Only after a boot up of the devcies and initial discovery will this work . So there are a few gotchas but basically it can work .



Hope this helps !

This message was edited by merlin on 3-5-09 @ 10:03 AM

[alexb_1]

I would be careful with spanning tree as you are going using the backplane (effectively a hub) in side the expansion unit. other then that I think it would work.

[mohamed.sabbah]

Merlin! I assume your suggested scenario is based on connecting the Ethernet port of the NBX chassis to say a switch port in hybrid mode which is member of both VLANS (both tagged), Is this assumption correct? Do you think that each digital card will start sending packets tagged with its corresponding VLAN (card1 tags VLAN1 while card2 tags VLAN2)over the same chassis port?

My other old question: If I do not connect the chassis Ethernet to the switch, but rather connect the Ethernet port on the digital card itself to the VLAN of first NBX, then do the same with th e second card but connect it to the VLAN of the second NBX, Will this work? (I want to use different VLANs to isolate the discovery problem conflict that you have described, and any other conflict issues that can arise)

Thanks

[merlin_1]

Yes that is what I am suggesting . but :



When you set up your network , make sure to have a default vlan for the tels to boot up . Thats why it gets tricky on the same network using 2 NBX systems so as long as you know your limitations , then you can work around them . The tels boot up and use the default vlan from the switch for arping out to the NBX(s). After the download they have the VLan tag ( if assigned ) . So the NBX needs to boot first then assign vlan second . Thats why I suggest back befor eto remove one NBX completely off the network and discover your devices . This is overcome after the original boot up of the devices assigned to the particular NBX .

This message was edited by merlin on 3-6-09 @ 6:59 AM