Interface flapping and always shows up/up even other side is shutdown

Question

Hi, there, I have a interface flapping issue in my network. 2 Cat3560 is connected through 2 trunk port configured with port-channel. When I shutdown one of port in Vlan100, other 2 ports in the same vlan will flap going up and down and OSPF will lose the neighbor. One thing I notice that is when I shutdown the switch port, on the other side of router, the L1-L2 is still up/up. I think it should be up/down. I have a keepalive setting on the router interface to 1800. Any body can give me some hints here to troubleshoot?
Here is the switch configs.
Building configuration...
no service pad
ip subnet-zero
ip routing
no ip domain-lookup
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
interface Port-channel1
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport trunk allowed vlan 100,200,300,400,600,700
switchport mode trunk
interface GigabitEthernet0/1
switchport access vlan 600
speed 100
duplex full
interface GigabitEthernet0/2
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/3
switchport access vlan 600
speed 100
duplex full
interface GigabitEthernet0/4
switchport access vlan 700
speed 100
duplex full
interface GigabitEthernet0/5
switchport access vlan 700
speed 100
duplex full
interface GigabitEthernet0/6
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/7
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/8
switchport access vlan 100
interface GigabitEthernet0/9
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/10
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/11
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/12
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/13
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/14
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/15
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/16
switchport access vlan 100
speed 100
duplex full
interface GigabitEthernet0/17
speed 100
duplex full
interface GigabitEthernet0/27
switchport access vlan 400
interface GigabitEthernet0/28
switchport access vlan 400
interface GigabitEthernet0/29
switchport access vlan 400
interface GigabitEthernet0/30
switchport access vlan 200
interface GigabitEthernet0/31
switchport access vlan 200
interface GigabitEthernet0/45
switchport access vlan 500
speed 100
duplex full
interface GigabitEthernet0/46
switchport access vlan 500
speed 100
duplex full
interface GigabitEthernet0/47
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport trunk allowed vlan 100,200,300,400,600,700
switchport mode trunk
channel-group 1 mode on
interface GigabitEthernet0/48
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport trunk allowed vlan 100,200,300,400,600,700
switchport mode trunk
channel-group 1 mode on
interface Vlan1
no ip address
shutdown
interface Vlan100
ip address 192.168.40.11 255.255.252.0
no ip redirects
no ip proxy-arp
standby 1 ip 192.168.40.1
standby 1 priority 110
standby 1 preempt
standby 1 track Vlan600 20
interface Vlan200
no ip address
interface Vlan600
ip address 192.168.35.1 255.255.255.0
router ospf 7
log-adjacency-changes
network 192.168.0.0 0.0.255.255 area 0
ip classless
=====================
When I shutdown interface gig 0/2, interface gig0/3 and gig0/4 will go down as well and come back online after a while.
Thanks for your help.

Answer 1

Your question is really missing a BUNCH of details, but I will take a stab at it:
1) Why on earth do you have a keepalive set to 1800 seconds on the router?
2) Your discussion and config above only talks about qty 2 c3560 switches. Where is the router in this topology?
3) You are going against several Cisco best practices here with your trunk ports:
a) I would never config a port-channel as mode 'on' because the switches will ignore any errors on the ports that would not keep the channel stable because you have configured them to hard set on. ALWAYS set the port channel to mode 'desirable silent'. The config needs to match on both ends of the link.
b) I would never config a port as a trunk mode 'on' without also running UDLD. It appears that your 2-port port-channel trunk above is using copper ports. You MUST enable UDLD on the copper gigabit ports manually (UDLD is enable by default on fiber gigabit ports). You may need to 'udld enable' globally on the switch depending on the IOS version. Obviously, as above, the same config needs to be done on both switches.
4) The log message that you get when you say ports g0/3 and g0/4 go down, is that for just VLAN 100 or are they line-protocol messages?
5) When port g0/2 goes down, are there any other ports in VLAN 100 still up?
6) What are the results of the following commands:
show int g0/3 switchport
show spanning-tree summary
show spanning-tree int po1
show spanning-tree int g0/2
show spanning-tree int g0/3
show spanning-tree int g0/4
show spanning-tree vlan 100
show spanning-tree vlan 600
show int status
show etherchannel summary
show etherchannel detail
show int trunk mod 0
Post more details and I'll try to help...