how to connect to LAN switch

[marika82_A]

hello,I'm trying to connect my switch catalist 2950 with University LAN so I could navigate!The problem is that to connect with University LAN means that my switch in reality must connect to University switch!Now I have activated in the port of my switch trunk mode but in this manner only hosts in default vlan (vlan 1)connect to Internet the others,in vlan 2 and 3 ,don't navigate.

So if I change configuration of the link to LAN in mode access the port on the switch becams amber color and no host can connect (also these in vlan 1).

How can I solve the problem?

[amit-singh]

Hi,

I think what going is that When you configure the 2950 as a trunk it sends a DTP (Dynamic trunking protocol ) frame and forms a trunk with its neighbour switch. The moment trunk is on you clients are able to go to the internet. The other vlan 2 and 3 are not able to go on to internet could be due to routing not enabled for these vlans and also may be these vlans are not allowed to go on to the internet.

When you make the port as an access port and it remains amber shows that your switch port and the neighbour switch's port are in different vlans. Now to really get on with this you should have access to your university switch and then accordingly do the neccessary configuration. For thhis moment you can try enabling the trunk on 2950 and have your Vlan1 clients access the internet. If you have access to university switch give us the config and we will let you know the necessary configuration.

HTH,

-amit singh

[marika82_A]

Hi,thank for your answer.

For me it's impossible to view the configuration of the University switch!

Perhaps one solution could be connect my swtich to a firewall?Here I have a firewall that connect to internet and I could try to connect the two devises together?

[amit-singh]

Yes,

You can try connecting the switch to your firewall. If you want to use Vlans on your switch make sure your firewall does the routing between those vlans otherwise you have to connect all the hosts in the same vlan. As far as your firewall is doing routing if you want implement vlans, you are abosulteky fine to go :-)

HTH,

-amit singh

[marika82_A]

ok infact now my hosts can navigate.If you have time i send you the design of my network so you can help me.

Now the problem is that the host in vlan 4 doesn't ping host in vlan 2 and 3,I believe the problem can solve whit confuring nat.Can you help me for this?

Ah another question, I'm confused about multicast configuration in the router (that you can see in the attachment)...can you help me?

thanks a lot

[amit-singh]

Hi,

If you are not able to ping between hosts in Vlan4 and the vlan 2/3, you need to check the routing part on your device which is doing the routing. Checking the diagram I see that your right might be doing the routing between these vlans. Make sure you have the sub-interface defined for your Vlan 4 on the router and is using the Vlan tag with the encapsulation command.

For, multicasting I can refer you some pages. I am not good at it as I have not practically implemented it in the field.

http://www.cisco.com/en/US/partner/products/hw/switches/ps708/products_configuration_guide_chapter09186a008007f319.html

regards,

-amit singh

[marika82_A]

Hi,thanks a lot.

I will check the routing,if I have problem with Nat configuration and routing can I send you a mail?

For next days I cannot work for my project I'm studing for my last university exame so I will continue after 17 August. If for you my request is not a problem I could contact you via mail. So if you are agree send me a mail with your mail address for your discretion.My mail address is marika82_A@libero.it.I hope in your help because in my university nobody follows me and nobody helps me for solve my problems:-(.

Sorry if I'm probably very insistent with you :-D.

P.S. ah my name is Marika.thanks for all

[marika82_A]

here there is the design