04-13-2011 03:33 PM - edited 03-06-2019 04:36 PM
I setup VLANs on Catalyst 3560 (8 port, PoE). The switch is connected vial trunk link to Brocade SuperX 800 switch. When I plug in a laptop to one of the Voip VLANs on 3560, it gets DHCP lease fine. If I plug in Polycomm phone instead, it doesn't get DHCP lease. If I setup static IP on the phone, the phone works fine. Why the phone doesn't get DHCP? It must be something not configured on the 3560, I just don't know what. the phone with DHCP works fine if connected directly to the Brocade switch. What am I missing on the 3560?
VLAN101 is VOIP vlan and FastEthernet0/1 port is was tested.
version 12.2
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Catalyst3560
!
!
no aaa new-model
system mtu routing 1500
ip subnet-zero
!
!
!
!
no file verify auto
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
interface FastEthernet0/1
switchport access vlan 101
switchport mode access
!
interface FastEthernet0/2
switchport access vlan 30
switchport mode access
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface GigabitEthernet0/1
switchport access vlan 30
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 30,101
switchport mode trunk
!
interface Vlan1
no ip address
shutdown
!
interface Vlan10
no ip address
!
interface Vlan30
ip address 172.16.80.5 255.255.252.0
!
ip classless
ip http server
!
!
control-plane
!
!
line con 0
line vty 0 4
login
line vty 5 15
login
!
end
Solved! Go to Solution.
04-20-2011 03:04 PM
Thanks for confirming the vvid!
Start up delay should be caused by Spanning-tree.
By default, with the original configuraiton posted for port f0/1, it could take up to 30-45 seconds to get connectivity to the network (a mix of STP and DHCP timers etc)
#spanning-tree portfast
is part of best practice host port configuration (I would recommend it being configured on all host ports in the network).
Benefits:
- reduce start up time -> port goes straight into forwarding instead of going through the STP state transitions, listening, learning etc
- does not generate a TCN upon link up or down (improves accuracy of TCN flag in STP topology and troubleshooting)
You'll also see this recommendation in Cisco IP Phone guides such as:
(contact web-help@cisco.com if unable to access)
HTH
Eugene.
04-21-2011 08:27 AM
Thank you again!
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