Configuring second vlan interface with ip

[ac1dh3ad]

Hi All,
I have following situation, switch 2950 (12.1(22)ea4a) has already default vlan and vlan interface with ip settings. Now i need one more vlan and vlan interface with ip from other subnet. Once i create vlan, vlan interface with ip settings and bring vlan interface up, switch drops telnet session and never come again. I wonder what causes switch to lose telnet session. I guess default vlan interface goes down, but not sure. All configuration is done remotely, so it preferable to keep switch accessible all the time without reboot. Please advise what steps should be taken to accomplish my task without losing telnet session and reboot?
Thx.

 

[North323]

post a config

 

[ac1dh3ad]

version 12.1
no service pad
no service timestamps debug uptime
service timestamps log datetime show-timezone
service password-encryption
service sequence-numbers
!
hostname sw01
!
enable secret 5 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
!
username admin privilege 15 password 7 xxxxxxxxxxxxxxxxxxxxxxx
ip subnet-zero
no ip source-route
!
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
!
!
interface FastEthernet0/1
no logging event link-status
no snmp trap link-status
spanning-tree portfast
...
interface FastEthernet0/48
no logging event link-status
no snmp trap link-status
spanning-tree portfast
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
ip address 192.168.0.251 255.255.255.0
no ip route-cache
!
ip default-gateway 192.168.0.254
no ip http server
!
line con 0
exec-timeout 0 0
password 7 xxxxxxxxxxxxxxxxxxxxxx
line vty 0 4
password 7 xxxxxxxxxxxxxxxxxxxxxx
line vty 5 15
password 7 xxxxxxxxxxxxxxxxxxxxxx
end

 

[North323]

how are you creating the second vlan? and what IP are you going to assign?

 

[lerdalt]

Are you wanting the 2950 to do the routing between the 2 vlans? If so, this isn't going to work. The 2950 isn't capable of the routing.

You can only setup one vlan interface with an IP address on the 2950. That is the interface used for management of the switch, no reason to have another vlan interface with another ip address on it.

You will want to create a second vlan on your VTP server, make certain you have both vlan's allowed on your trunk interfaces. Verify the new vlan is on the 2950, then just configure the individual access ports to the vlan you want the hosts to be connected on.

 

[ac1dh3ad]

I know that 2950 is a l2 switch and does not have ability to route between vlans. I dont even want this. If you say that it is not possible to create two vlan interfaces with different ips, then i will say that i have two configured on 2960. Suppose i want my switch to be accessible from two different subnets. I follow as
vlan 2
interface fa0/4
swi mode acc
swi access vlan 2
interface vlan 2
ip address 192.168.1.251 255.255.255.0
no shutdown
...

 

[North323]

post your sh vlan so basically when you add in your above commands you lose vlan 1?

 

[ac1dh3ad]

VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
Fa0/25, Fa0/26, Fa0/27, Fa0/28
Fa0/29, Fa0/30, Fa0/31, Fa0/32
Fa0/33, Fa0/34, Fa0/35, Fa0/36
Fa0/37, Fa0/38, Fa0/39, Fa0/40
Fa0/41, Fa0/42, Fa0/43, Fa0/44
Fa0/45, Fa0/46, Fa0/47, Fa0/48
Gi0/1, Gi0/2
2 VLAN0002 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0

Basically vlan interface 1 goes down, and i lose telnet session.

 

[North323]

ok how many other switches do you have? post your sh vtp satus

 

[unclerico]

as lerdalt said, only one SVI is active at any one time on a 2950. You can give IP addresses to your VLANs all day, but in the end only one can be active at a time.

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[burtsbees]

That's right---you will notice that after creating two SVI's in an L2 switch, you do a no shut on both, then do a sh run, you will see that the first one will be shutdown.

Burt

 

[ac1dh3ad]

Then how do u explain that i have two interfaces up on 2960 which is l2 switch.

 

[unclerico]

2950 <> 2960

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[lerdalt]

I don't have as much exposure to the 2960's, can you post a show run from it for us to look at?

 

[lerdalt]

one more thought too..you said you want your switch accessible from 2 different vlans. How are you routing between the 2 vlans? If routing is working, then you don't need to have 2 management addresses on the switch.

 

[burtsbees]

Interfaces, or vlans? I have 24 interfaces up in my 2950, 78 in my 2980G, both L2...

You don't have two vlan SVI interfaces up in your 2960, I guarantee it. Post a sh run and a sh int for both vlans...I wanna see this...

Burt

 

[vipergg]

Just post a show ip int brief and that will tell if you have more than 1 SVI active at a time .