Intermittent Connection Problem Between Active/Stanby LTM 1600 and a pair of Cisco 2960

I have a pair of LTM 1600 (namely LTM-A & LTM-B) running in active/standby mode and a two pair of Cisco2960 (namely WAN-2960-A, WAN-2960-B, LAN-2960-A & LAN-2960-B). My setup is as below:-

 

 

Network Interconnection:-

 

LTM-A Interface 1.1 -> WAN-2960-A Port 1

 

LTM-B Interface 1.1 -> WAN-2960-B Port 1

 

LTM-A Interface 2.1 (Fibre) -> LTM-B Interface 2.2 (Fibre)

 

LTM-A Interface 2.2 (Fibre) -> LTM-B Interface 2.2 (Fibre)

 

LTM-A Interface 1.3 (internal-trunk) -> LAN-2960-A Port 1 (ether-channel Port-channel 3)

 

LTM-A Interface 1.4 (internal-trunk) -> LAN-2960-A Port 2 (ether-channel Port-channel 3)

 

LTM-B Interface 1.3 (internal-trunk) -> LAN-2960-B Port 1 (ether-channel Port-channel 3)

 

LTM-B Interface 1.4 (internal-trunk) -> LAN-2960-B Port 2 (ether-channel Port-channel 3)

 

LAN-2960-A Port 3 (ether-channel Port-channel 5) -> LAN-2960-B Port 3 (ether-channel Port-channel 5)

 

LAN-2960-A Port 4 (ether-channel Port-channel 5) -> LAN-2960-B Port 4 (ether-channel Port-channel 5)

 

 

LTM-A & LTM-B:-

 

Trunk List: trunk interface 2.1 & 2.2 named as Fibre, trunk interface 1.3 & 1.4 named as internal-trunk

 

Trunk Setting: LACP: Enable, LACP Mode: Active, LACP Timeout: Long, Link Selection Policy: (Auto), Frame Distribution Hash: (Source/Destination IP Address)

 

 

VLAN List:

 

Internal, Tag: 4093, Untagged Interface: internal-trunk, MTU:1500, Fail-safe: Enable, Fail-safe-timeout: 15, Action: Failover

 

External, Tag: 10, Untagged Interface: 1.1, MTU: 1500, Fail-safe: Enable, Fail-safe-timeout:15, Action: Failover

 

pri-failover, Tag: 4092, Untagged Interface: Fibre, Fail-safe: Disable

 

All interface running at 1G full-duplex

 

 

part of show run for LAN-2960-A & LAN-2960-B:-

 

LAN-2960-Ashow run

 

vtp domain f5-private

 

vtp mode transparent

 

spanning-tree mode pvst

 

spanning-tree extend system-id

 

port-channel load-balance src-dst-ip

 

vlan 4093

 

name f5-private-vlan

 

!

 

interface Port-channel3

 

switchport trunk native vlan 4093

 

switchport mode trunk

 

no keepalive

 

flowcontrol receive desired

 

!

 

interface Port-channel5

 

switchport access vlan 4093

 

switchport mode access

 

!

 

interface GigabitEthernet1/0/1

 

switchport trunk native vlan 4093

 

switchport mode trunk

 

flowcontrol receive desired

 

spanning-tree portfast disable

 

channel-group 3 mode active

 

!

 

interface GigabitEthernet1/0/2

 

switchport trunk native vlan 4093

 

switchport mode trunk

 

flowcontrol receive desired

 

spanning-tree portfast disable

 

channel-group 3 mode active

 

!

 

interface GigabitEthernet1/0/3

 

switchport access vlan 4093

 

switchport mode access

 

spanning-tree portfast disable

 

channel-group 5 mode desirable non-silent

 

!

 

interface GigabitEthernet1/0/4

 

switchport access vlan 4093

 

switchport mode access

 

spanning-tree portfast disable

 

channel-group 5 mode desirable non-silent

 

!

 

interface GigabitEthernet1/0/5 - 1/0/24

 

switchport access vlan 4093

 

switchport mode access

 

spanning-tree portfast

 

!

 

interface Vlan4093

 

ip address 192.168.96.1 255.255.255.0

 

!

 

LAN-2960-Ashow vlan

 

 

VLAN Name Status Ports

 

---- -------------------------------- --------- -------------------------------

 

1 default active Gi1/0/25, Gi1/0/26, Gi1/0/27

 

Gi1/0/28

 

1002 fddi-default act/unsup

 

1003 token-ring-default act/unsup

 

1004 fddinet-default act/unsup

 

1005 trnet-default act/unsup

 

4093 f5-private-vlan active Gi1/0/5, Gi1/0/6, Gi1/0/7

 

Gi1/0/8, Gi1/0/9, Gi1/0/10

 

Gi1/0/11, Gi1/0/12, Gi1/0/13

 

Gi1/0/14, Gi1/0/15, Gi1/0/16

 

Gi1/0/17, Gi1/0/18, Gi1/0/19

 

Gi1/0/20, Gi1/0/21, Gi1/0/22

 

Gi1/0/23, Gi1/0/24, Po5

 

 

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2

 

---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------

 

1 enet 100001 1500 - - - - - 0 0

 

1002 fddi 101002 1500 - - - - - 0 0

 

1003 tr 101003 1500 - - - - srb 0 0

 

1004 fdnet 101004 1500 - - - ieee - 0 0

 

 

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2

 

---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------

 

1005 trnet 101005 1500 - - - ibm - 0 0

 

4093 enet 104093 1500 - - - - - 0 0

 

 

Remote SPAN VLANs

 

------------------------------------------------------------------------------

 

 

 

Primary Secondary Type Ports

 

------- --------- ----------------- ------------------------------------------

 

 

LAn-2960-Ashow vtp status

 

VTP Version capable : 1 to 3

 

VTP version running : 1

 

VTP Domain Name : f5-private

 

VTP Pruning Mode : Disabled

 

VTP Traps Generation : Disabled

 

Configuration last modified by 0.0.0.0 at 3-8-93 22:38:54

 

 

Feature VLAN:

 

--------------

 

VTP Operating Mode : Transparent

 

Maximum VLANs supported locally : 255

 

Number of existing VLANs : 5

 

Configuration Revision : 0

 

 

 

 

All server have dual interface connecting to LAN-2960-A and LAN-2960-B using interface bonding mode 6 miimon=100. Found that there are consistent packet drop for both LTB as below:-

 

 

Interface Statistics 　 Bits Packets Multicast Errors Drops 　

 

Name Status In Out In Out In Out In Out In Out Collisions

 

mgmt DOWN 0 0 0 0 0 0 0 0 0 0 0

 

1.1 UP 358.4G 4.5T 291.9M 446.2M 8.2M 5.9K 0 0 59.0K 444 0

 

1.2 DOWN 0 0 0 0 0 0 0 0 0 0 0

 

1.3 UP 2.2T 196.1G 241.1M 153.9M 880.0K 26.6K 0 0 309.9K 1.5K 0

 

1.4 UP 2.4T 277.5G 249.8M 164.9M 111.5K 16.7K 0 0 58.6K 821 0

 

2.1 UP 19.0M 19.0M 20.4K 20.4K 17.7K 17.8K 0 0 0 0 0

 

2.2 UP 11.6G 11.9G 11.6M 11.7M 16.7K 16.7K 0 0 0 0 0

 

 

ON LAN-2960-A there are 408 packet drop on interface 1 and 175 packet drop on interface 2 (connecting LTM) while all other interface record 0 packet drop. I would like to know what seems to be the problem? I have also tried to swapping another UTP cable while still encounter intermittent connection drop. Am my configuration correct?