The 1841 is a router and not

ladopetrucci · ‎01-12-2016

hello , I have cisco 1841 router with IOS c1841-adventerprisek9-mz.151-3.T2.bin

I have problem with defaul Vlan , it doesn't exist, can you help me for this case?

this is output - sh ip int brief

CCNP#sh ip int brief
Interface IP-Address OK? Method Status Prot
ocol
FastEthernet0/0 192.168.2.200 YES NVRAM up up

FastEthernet0/1 unassigned YES NVRAM administratively down down

Serial0/0/0 unassigned YES NVRAM administratively down down

Seb Rupik · ‎01-12-2016

Hi there,

if you want to enable VLAN tagging on the interfaces you will need to configure them as sub-interfaces. Eg; If you wanted to create a router interface on fa0/0 in VLAN10 and tag those packets, try this configuration:

!
int fastethernet0/0.10
 encapsulation dot1q 10
 ip address 192.168.10.254 255.255.255.0
 no shut
!

cheers,

Seb.

ladopetrucci · ‎01-12-2016

No, I want make managment ip address woth vlan 1 but there is no vlan . When i type command " int vlan 1" , error is appears.

Karsten Iwen · ‎01-12-2016

The 1841 is a router and not a switch. It has routed ports and no vlan-interfaces (unless you insert a switch-module into one of the slots).

Seb Rupik · ‎01-12-2016

Ah OK, try this:

!
ip vrf management
 description management VRF
!
!
int fa0/0
 no shut
 ip vrf forwarding management
 ip address 192.168.2.200 255.255.255.0
!
int fastethernet0/0.10
 encapsulation dot1q 10
 ip address 192.168.10.254 255.255.255.0
 no shut
!

You need to create a sub-interface to get IOS to tag VLAN1 on fa0/0. You can confirm this:

r3#sh int fa0/0

...
FastEthernet0/0 is up, line protocol is down 
 Hardware is Gt96k FE, address is 001e.4a8c.1726 (bia 001e.4a8c.1726)
 Internet address is 192.168.1.254/24
 MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec, 
 reliability 255/255, txload 1/255, rxload 1/255
 Encapsulation 802.1Q Virtual LAN, Vlan ID 1., loopback not set
 Keepalive set (10 sec)
...

If you don't want to create VLAN10, then explicitly create the VLAN1 sub-interface:

!
int fastethernet0/0.1
 encapsulation dot1q 1
 ip vrf forwarding management
 ip address 192.168.2.200 255.255.255.0
 no shut
!

r3#sh int fa0/0.1
FastEthernet0/0.1 is up, line protocol is down 
 Hardware is Gt96k FE, address is 001e.4a8c.1726 (bia 001e.4a8c.1726)
 MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec, 
 reliability 255/255, txload 1/255, rxload 1/255
 Encapsulation 802.1Q Virtual LAN, Vlan ID 1.

cheers,

Seb.

Please rate helpful posts :)

Glenn Martin · ‎01-12-2016

Moving discussion to the Network Infrastructure>WAN,Routing community for greater visibility