From: Roberto Giana (Roberto.Giana@econis.com)
Date: Wed Feb 05 2003 - 16:00:32 GMT-3
Hi Matthew
Hmm.... I would recommend to turn off "spanning-tree portfast" on the trunks
and enable "spanning-tree portfast" on the access ports. The portfast
feature was intended for access ports, not for uplink ports.
It's a known issue, that clients can have problems with getting an IP when
booting up without the portfast feature activated on their access ports.
In your situation I would do further investigations after that.
Best regards
Roberto
-----Original Message-----
From: Matthew Poole [mailto:matthew.poole@blueyonder.co.uk]
Sent: Mittwoch, 5. Februar 2003 11:36
To: ccielab@groupstudy.com
Subject: OT:Catalyst and DHCP forwarding.
I realise it's a little off topic but thought I'd give you all a crack at
this
one.
I have a colleague who has been configuring 2 2950's. They are connected
together via a dot1q trunk and they both have just 2 VLAN's. Two PC's on
separate VLAN's on S1 can get DHCP addresses from servers in S2 which are in
the same VLAN's - i.e. PC 1 and Server 1 in VLAN 1, PC 2 and server 2 in
VLAN
2 - no intervlan routing.
This all works fine on 12.05, however when he upgrades to 12.1 (he tried 4
versions) the PC in VLAN 2 can no longer get an IP address from the DHCP
server, VLAN 1 works fine. Interestingly, pings within VLAN 2 work fine if
he
gives the PC a static address.
He has had this same issue with 3550's and 4500's as well on 2 other sites -
if anybody has done this uograde and had this same issue we'd love to here
from you and how you got round it.
The configs are below, the only thing I can see are portfast on the trunk
and
no switchport mode access on the access ports. As I said previously it's
only
when he upgrades that he has these problems - they work fine on 12.05.
SWITCH 1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname switch1
!
vtp mode transparent
!
vlan 2
vlan 3
!
interface FastEthernet0/1
description *** 802.1Q Port ***
switchport trunk encapsulation dot1q
switchport mode trunk
spanning-tree portfast
no ip address
!
interface FastEthernet0/2
description *** Access Port VLAN 1 ***
switchport access vlan 1
!
interface FastEthernet0/3
description *** Access Port VLAN 2 ***
switchport access vlan 2
!
Other ports as above
!
interface Vlan1
ip address 192.168.1.1 255.255.255.0
no ip route-cache
!
------------------------------------------------------------
SWITCH 2
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname switch2
!
vtp mode transparent
vlan 2
vlan 3
!
interface FastEthernet0/1
description *** 802.1Q Port ***
switchport trunk encapsulation dot1q
switchport mode trunk
spanning-tree portfast
no ip address
!
interface FastEthernet0/2
description *** Access Port VLAN 1 ***
switchport access vlan 1
!
interface FastEthernet0/3
description *** Access Port VLAN 2 ***
switchport access vlan 2
!
Other ports as above
!
interface Vlan1
ip address 192.168.1.2 255.255.255.0
no ip route-cache
.
.
This archive was generated by hypermail 2.1.4 : Sat Mar 01 2003 - 11:06:10 GMT-3