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Switch to Router Connectivity issues

Hey all, im in a situation where i have 2 switches, connected to the same router, routing the same vlans.  Now i have bridge groups connecting my 2 switches to the router for redundancy.

c7000----------SWITCH1----------ROUTER
        ^---------SWITCH2---------^     <--connected to same router

when i enable the port on switch1 connected to the router to start working, it works fine, the router routes between vlans fine all is good.  But when i enable the port on switch2 connected to the router to start working, if all works fine for about 30secs then they both disable and stop working.  When i do "Sh int" for the ports connecting to the router it says "DISABLED-ERR".  How do i get both switches working/routing the same vlans??
The aim is to route all data from the c7000 ova either switch for redundancy and back either path.  The Hardware setup is correct.  Attached is the switch and router config.
ANY HELP WILL BE REALLY APPRECIATED!
no aaa new-model
switch 1 provision ws-c3750g-24ps
switch 2 provision ws-c3750g-24ps
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 Port-channel1
 description TO ROUTER
 switchport trunk encapsulation dot1q
 switchport mode trunk
 flowcontrol receive desired
 spanning-tree portfast trunk
!
interface Port-channel2
 description UPLINK_VC_A
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 spanning-tree portfast trunk
!
 description UPLINKVC_B
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 spanning-tree portfast trunk
!
interface Port-channel4
 description UPLINK_VC_C
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 spanning-tree portfast trunk
!
interface Port-channel5
 description UPLINK_VC_D
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/1
 description VC-B1-1
switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 2 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/2
 description VC-B1-2
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 2 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/3
 description VC-B2-1
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 3 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/4
VC-B2-2
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 3 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/5
 description VC-B3-1
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 4 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/6
 description VC-B3-2
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 4 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/7
 description VC-B4-1
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 5 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/8
 description VC-B4-2
 switchport access vlan 10
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 5 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet1/0/9
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/10
 switchport access vlan 10
switchport mode access
!
interface GigabitEthernet1/0/11
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/12
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/13
 description TAPE_iLO
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet1/0/14
 description EVA_WEB_OCP
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet1/0/15
 description OA_c7000_RIGHT
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet1/0/16
 description Brocade_FB
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet1/0/17
 description MGMT_SERVER_NIC_1
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet1/0/18
 description c7000_UPS_MGMT_UPPER
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet1/0/19
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/20
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/21
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/22
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/23
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet1/0/24
 switchport access vlan 10
 switchport mode access
interface GigabitEthernet1/0/25
!
interface GigabitEthernet1/0/26
!
interface GigabitEthernet1/0/27
 description LINK_PatchingRoom
!
interface GigabitEthernet1/0/28
 description ROUTER
 switchport trunk encapsulation dot1q
 switchport mode trunk
 flowcontrol receive desired
 channel-group 1 mode on
!
interface GigabitEthernet2/0/1
 description VC-B1-3
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 2 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet2/0/2
 description VC-B1-4
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 2 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet2/0/3
 description VC-B2-3
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 3 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet2/0/4
 description VC-B2-4
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 3 mode active
 spanning-tree portfast trunk
 
interface GigabitEthernet2/0/5
 description VC-B3-3
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 4 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet2/0/6
 description VC-B3-4
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 4 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet2/0/7
 description VC-B4-3
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 5 mode active
 
!
interface GigabitEthernet2/0/8
 description VC-B4-4
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 10,11
 switchport mode trunk
 channel-group 5 mode active
 spanning-tree portfast trunk
!
interface GigabitEthernet2/0/9
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/10
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/11
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/12
switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/13
 description Brocade_Swch_FA
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet2/0/14
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet2/0/15
 description EVA_UPS_MGMT
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet2/0/16
 description EVA_UPS_MGMT_2
 switchport access vlan 10
switchport mode access
!
interface GigabitEthernet2/0/17
 description MGMT_SVR_NIC2
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet2/0/18
 description c7000_UPS_MGMT_LOWER
 switchport access vlan 10
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet2/0/19
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/20
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/21
switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/22
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/23
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/24
 switchport access vlan 10
 switchport mode access
!
interface GigabitEthernet2/0/25
!
interface GigabitEthernet2/0/26
!
interface GigabitEthernet2/0/27
!
interface GigabitEthernet2/0/28
 description ROUTER
switchport trunk encapsulation dot1q
 switchport mode trunk
 flowcontrol receive desired
 channel-group 1 mode on
!
interface Vlan1
 no ip address
!
interface Vlan10
 ip address 10.112.234.13 255.255.255.0
!
ip default-gateway 10.112.234.1
ip classless
ip route 0.0.0.0 0.0.0.0 10.112.234.1
ip http server
!

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router.TXT
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Thunder-Cat
Asked:
Thunder-Cat
2 Solutions
 
Aaron StreetInfrastructure ManagerCommented:
try a show log

this will tell you why the port it err disabeling

 there are a few resons

you can do a show err-disable detection (i think it detection but try sh err-disabble ? to check)

that will show you what things are monitored for err-disable.

I would guess it might be that the switch is seeing the same mac address on two ports, so it will shut one down.
but a show logs will tell you what has happened.

also dont reboot the switch, You will lose the logs (unless you have set them up to save to non volitila memory or to soem where off the switch!
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Aaron StreetInfrastructure ManagerCommented:
It jsut so happend I have a nice example of a BPDU insidence on one of my switchs causing a err-disablable. As you can see in the show log below, it sees a violation of the BPDU and disababels the port.

also hear a link to some more about err-disabables

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a00806cd87b.shtml

if you cant get to that link let me know and I will get a copy for you
3750 switch#show log
Syslog logging: enabled (0 messages dropped, 0 messages rate-limited, 0 flushes,
 0 overruns)
    Console logging: level debugging, 129 messages logged
    Monitor logging: level debugging, 0 messages logged
    Buffer logging: level debugging, 129 messages logged
    Exception Logging: size (4096 bytes)
    File logging: disabled
    Trap logging: level informational, 130 message lines logged
 
Log Buffer (4096 bytes):
UARD: Received BPDU on port FastEthernet1/0/4 with BPDU Guard enabled. Disabling
 port.
*Apr 18 00:02:06.410: %PM-4-ERR_DISABLE: bpduguard error detected on Fa1/0/4, pu
tting Fa1/0/4 in err-disable state
*Apr 18 00:02:07.417: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthern
et1/0/4, changed state to down

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Thunder-CatAuthor Commented:
Hey thanks for the reply :) interesting what your saying,im not at work atm so cant try the show log command which i will do but i remember when the error came up it says that, "po1 port is flapping with port such and such ( afair few different ports) and then displays mac addresses and when i do "sh bridge" no mac addresses appear.
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Aaron StreetInfrastructure ManagerCommented:
in which case it is simple that is it seeing a mac addrss jumping between ports.

this may be due to having portfast turned on on the switch, (oh i noticed your other question ;) ) see my reply there..

no no no portfast on switch to switch links!! this will be the problem. Post-fast assumes a single device connected to the port. when you connect another switch it is seeing more than one mac address. it will nto liek that and think there is an error..

turn of portfast and i bet it will be fine.
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from_expCommented:
btw, take a look here http://h20000.www2.hp.com/bc/docs/support/SupportManual/c01386629/c01386629.pdf
about how to connect VCs to cisco switch
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Thunder-CatAuthor Commented:
Ive disabled portfast on all ports and still no joy.  I have a channel-group configured on the switches to goto the router, now do i need one to go back to the switches??
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Aaron StreetInfrastructure ManagerCommented:
if you have a duel link, then you will need to either set up spanning tree to block on of the ports. Or set up a port channel group.

if you turn of spanning tree, and done have a channel group on a duel link you will get probelms. no matter where the linsk are comming to or from..
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microITCommented:
I know this is old and closed but I want to ask a question related to this, I understand if it can't be answered in the same thread but thought i'd try anyway.  Is portfast OK on a switchport connected to a router?  Will it cause any issues (i.e. performance, etc)?
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Aaron StreetInfrastructure ManagerCommented:
no.

portfast is simple telling the port to skip spanning tree checks, and put the port directly in to a forwarding state. It has no affect on the actuly proformance of the link.

The only issue you may have is that if you create a loop in the network with ports that are port fast! Spanning tree will not then block them and you can will have issues. but if you are carefull then there is no reson no to have portfast enababled.
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