HELP!cisco 2811 with 2 fast ethernet ports and 4 vlans

[desertscorpio]

I need urgent help on this. I have a brand new cisco 2811 with 2 FE ports. The port f0/0 is connected to the internet and the f0/1 will be connected to the switch which has 4 vlans configured on it. I have no idea how to go about doing this. Can someone please help me with the configuration on the router. My responsibility is to configure the following:
* A trunk on the router for the vlans.
* 4 sub interfaces with IP address on the router.
* Route this vlans out of the network.
Our devices are hosted in a datacentre.Now we are going to place a cisco 2811 in the datacentre which will be uplinked to the backbone switch of the upstream provider.The cisco 2811 should carry vlans from a remote NO to the internet.It is something like this:-

Backbone switch---->(f0/0)Cisco 2811(f0/1)--(trunk)--(Remote switch)[vlan1,vlan2,vlan3,vlan4]

Now my queries are
*On the f0/1 do I configure anything or I directly create start creating sub-interfaces with the IP Addresses?

* What kind of encapsulation do I use on the vlans?

* For this network we have a class 'C'(/24), I want to subnet them into 4 subnets.

* I know I can use static routes on the router but can someone please tell me what will be my next hop?Will it be the f0/0 or the IP address of the back bone switch.

 

[plshlpme]

youll want to create 4 subinterfaces on your fa0/1

and split your /24 into 4 /26's
so your mask will be 255.255.255.192

network address' are .0 .64 .128 .192

i would assign the first usable address to each subinterface
.1 .65 .129 .193

then use dot1q trunking with the vlan number.

for your clients the gw should be the fa0/1 ip for its corresponding vlan.

 

[desertscorpio]

Thank you so much for your reply, but how do I route these subnets out? Should I give a default route or static routes?

 

[plshlpme]

i assume your provider is routing the class c to you??
if so then all youll need is a default route back to them in your 2811

 

[desertscorpio]

thanx plshlpme. So the configuration will be somehing like this

int f0/1.1
ip address 192.168.10.1 255.255.255.0
encapsulation dot1q 1(vlan number)

int f0/1.2
ip address a.b.c.d 255.255.255.240 secondary
encapsulation dot1q 2-->This is the vlan number?

int f0/1.3
ip address a.b.c.d 255.255.255.240 secondary
encapsulation dot1q 2-->This is the vlan number?

int f0/1.4
ip address a.b.c.d 255.255.255.240 secondary
encapsulation dot1q 2-->This is the vlan number?


ip route 0.0.0.0 0.0.0.0 (provider class c IP)

 

[plshlpme]

well each subinterface wouldn't be a secondary address.
they are logically seperate so each ip is the primary for that interface.

your correct the number after the dot1q is the vlan number.
and the ip route statement is correct use the ip that the provider uses on their end of the link. (your next hop)


im assuming a couple things here.
a - the provider gave you a /30 subnet for your wan link
b - you want to evenly distribute your /24 into 4 subnets on 4 vlans on the lan

int fa0/0
ip address a.a.a.a 255.255.255.252 (provided by isp)

int f0/1
no ip address

int f0/1.1
ip address 192.168.10.1 255.255.255.192
encapsulation dot1q 1(vlan number)

int f0/1.2
ip address 192.168.10.65 255.255.255.192
encapsulation dot1q 2

int f0/1.3
ip address 192.168.10.129 255.255.255.192
encapsulation dot1q 3

int f0/1.4
ip address 192.168.10.225 255.255.255.192
encapsulation dot1q 4

ip route 0.0.0.0 0.0.0.0 a.a.a.b

the only other config will be on your switch. the port between the router and the switch will need to be put into trunk mode, and youll need to assign your vlans to your interfaces.

i can't test the above.. but it looks good to me..