06-26-2008 11:27 PM - edited 03-05-2019 11:51 PM
Hi all,
I have been implementing a new Cisco 3560 this morning. The switch is setup using OSPF and connectd to a Cisco 3550 over a VLAN interface.
My question is - i have 12 other VLANs and VLAN interfaces on the switch. None of these come 'up' unless there is an active device in the VLAN. Is this correct? I usually configure one VLAN as a management VLAN and assign that an IP address, but i can't even get to that unless i put a device in the VLAN.
The 3560 itself can see all other routes in the network when i do Show Ip Route OSPF, and the OSPF adjacency is fine, but i cannot get back to any of the VLAN interfaces on the switch unless i plug a device into each VLAN...
Any help much appreciated, can post configs if this helps,
Cheers
Jonathan
06-26-2008 11:55 PM
Hi Jonathan,
AFAIK, This is expected. You need to have atleast one active interface configured to be part of this vlan in order to get the vlan interface (SVI) up.
Alternately, IF you have any trunk interface configured and up, all SVIs will be up.
Is there any specific reason (like testing purpose) why you need reachability for a vlan which doesnt have any active device?.
Regards,
Nagendra
06-27-2008 12:02 AM
Hi,
Thanks for the response. We are currently testing at the moment, so would be handy to see them all. We also like to have a management VLAn, in this case VLAN 12, that is always available for monitoring etc.
The link connecting back to the main site is a trunk link:
interface FastEthernet0/48
description Connection to NP LES 100
switchport trunk encapsulation dot1q
switchport trunk native vlan 34
switchport trunk allowed vlan 10,11,34,999
switchport mode trunk
speed 100
duplex full
srr-queue bandwidth share 1 70 25 5
srr-queue bandwidth shape 3 0 0 0
priority-queue out
mls qos trust dscp
VLAN 34 is our OSPF vlan, and i thought that by having this, all other VLAN inerfaces would come up. The trunked link is up, as we can ping over the VLAN 34 interfaces. THe switchport allowed VLAN statement only allows the OSPF VLAN and a couple of other specialist vlans across, but that is how it shoudl be as far as i know...
Cheers
JOnathan
06-27-2008 01:53 AM
" switchport trunk allowed vlan 10,11,34,999 "
In your config, vlan 12 is not in allowed vlan list of your trunk. As you dont have any other interface configured to be part of vlan 12 and your trunk doesnt have this vlan in allowed list, it is expected that the SVI will not be up.
Having either of the above will bring the SVI up.
HTH,
Nagendra
06-27-2008 06:40 AM
Thanks very much. We have placed a switch behind this one with a trunked link allowing all VLANs in, this has brought all of the SVI's up, so we are all sorted there.. just got to get the phones working now!
Cheers
Jonboy
06-27-2008 07:34 AM
Have you setup VTP on these devices
!
vlan database
!
vtp domain yourdomainname
!
vtp domain yourpassword
!
vtp domain server or client
!
exit
!
Have you implemented this management?
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