To troubleshooting EtherChannel, you need to looking for assessing ports, and they will not
be mixed with one port green and another port orange (Take a look at topology diagram)

To troubleshooting EtherChannel, you would like to trying to find assessing ports, and that they won’t
be mixed with one port green and another port orange (Take a glance at topology diagram)

Step 1: Set port to trunking mode.

a. Verify that each one the physical ports within the topology are set to trunking and proper any access mode.

S2
S2>en
S2#config t
Enter configuration commands, one per line. End with CNTL/Z.
S2(config)#int range f0/21 – 24
S2(config-if-range)#switchport mode trunk

S2(config-if-range)#int range gi0/1-2
S2(config-if-range)#switchport mode trunk

b. Correct any EtherChannel port aren’t set to trunking mode

S1
S1>en
S1#config t
Enter configuration commands, one per line. End with CNTL/Z.
S1(config)#int port-channel 1
S1(config-if)#switchport mode trunk
S1(config-if)#

S2
S2(config)#int port-channel 2
S2(config-if)#switchport mode trunk
S2(config-if)#int port-channel 3
S2(config-if)#

S2(config-if)#switchport mode trunk
S2(config-if)#int port-channel 6
S2(config-if)#switchport mode trunk
S2(config-if)#

Step 2: Correct and Identify Port Channel Assignment Issue on S1, S2, S3 and S4.

To Identify and proper port-channel assignment issue use command
show etherchannel summary

S1
S1(config-if)#do show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – did not allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

1 Po1(SD) LACP Gig0/1(I) Gig0/2(I)
3 Po3(SU) LACP Fa0/23(P) Fa0/24(P)
5 Po5(SU) LACP Fa0/21(P) Fa0/22(P)

S2
S2(config-if)#do show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – did not allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

2 Po2(SU) LACP Gig0/1(P) Gig0/2(P)
3 Po3(SU) LACP Fa0/23(P) Fa0/24(P)
6 Po6(SD) LACP Fa0/21(I) Fa0/22(I)

S3
S3>en
S3#show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – did not allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

1 Po1(SD) PAgP Gig0/1(I) Gig0/2(I)
4 Po4(SD) PAgP Fa0/23(I) Fa0/24(I)
6 Po6(SD) PAgP Fa0/21(I) Fa0/22(I)

S4
S4>en
S4#show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – did not allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

2 Po2(SU) LACP Gig0/1(P) Gig0/2(P)
4 Po4(SU) LACP Fa0/21(P) Fa0/22(P) Fa0/23(I) Fa0/24(I)
5 Po5(SD) –

Step 3: Correct Port Channel Assignments on S4.

S4
S4#config t
Enter configuration commands, one per line. End with CNTL/Z.
S4(config)#int range fa0/21 – 22
S4(config-if-range)#channel-group 5 mode active
S4(config-if-range)#

Step 4: Correct and Identify Port Channel Protocol Issue on S3

To identify the protocol issues use the command show etherchannel summary

S3#show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – did not allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

1 Po1(SD) PAgP Gig0/1(I) Gig0/2(I)
4 Po4(SD) PAgP Fa0/23(I) Fa0/24(I)
6 Po6(SD) PAgP Fa0/21(I) Fa0/22(I)

a. Correct protocol issues on S3

S3
S3#config t
Enter configuration commands, one per line. End with CNTL/Z.
S3(config)#int range gi0/1 – 2
S3(config-if-range)#no channel-group
S3(config-if-range)#channel-group 1 mode active
S3(config-if-range)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up

S3(config-if-range)#int range fa0/21 – 22
S3(config-if-range)#no channel-group
S3(config-if-range)#channel-group 6 mode active
S3(config-if-range)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/21, changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/21, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/22, changed state to down

S3(config-if-range)#int range fa0/23 – 24
S3(config-if-range)#no channel-group
S3(config-if-range)#channel-group 4 mode active
S3(config-if-range)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/23, changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/23, changed state to up

To troubleshooting EtherChannel, you need to looking for assessing ports, and they will not
be mixed with one port green and another port orange (Take a look at topology diagram)

Step 1: Set port to trunking mode.

a. Verify that all the physical ports in the topology are set to trunking and correct any access mode.

S2

S2>en
S2#config t
Enter configuration commands, one per line. End with CNTL/Z.
S2(config)#int range f0/21 – 24
S2(config-if-range)#switchport mode trunk

S2(config-if-range)#int range gi0/1-2
S2(config-if-range)#switchport mode trunk

b. Correct any EtherChannel port are not set to trunking mode

S1

S1>en
S1#config t
Enter configuration commands, one per line. End with CNTL/Z.
S1(config)#int port-channel 1
S1(config-if)#switchport mode trunk
S1(config-if)#

S2

S2(config)#int port-channel 2
S2(config-if)#switchport mode trunk
S2(config-if)#int port-channel 3
S2(config-if)#

S2(config-if)#switchport mode trunk
S2(config-if)#int port-channel 6
S2(config-if)#switchport mode trunk
S2(config-if)#


Step 2: Correct and Identify Port Channel Assignment Issue on S1, S2, S3 and S4.

To Identify and correct port-channel assignment issue use command
show etherchannel summary

S1

S1(config-if)#do show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – failed to allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

1 Po1(SD) LACP Gig0/1(I) Gig0/2(I)
3 Po3(SU) LACP Fa0/23(P) Fa0/24(P)
5 Po5(SU) LACP Fa0/21(P) Fa0/22(P)

S2

S2(config-if)#do show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – failed to allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

2 Po2(SU) LACP Gig0/1(P) Gig0/2(P)
3 Po3(SU) LACP Fa0/23(P) Fa0/24(P)
6 Po6(SD) LACP Fa0/21(I) Fa0/22(I)

S3

S3>en
S3#show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – failed to allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

1 Po1(SD) PAgP Gig0/1(I) Gig0/2(I)
4 Po4(SD) PAgP Fa0/23(I) Fa0/24(I)
6 Po6(SD) PAgP Fa0/21(I) Fa0/22(I)

S4

S4>en
S4#show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – failed to allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

2 Po2(SU) LACP Gig0/1(P) Gig0/2(P)
4 Po4(SU) LACP Fa0/21(P) Fa0/22(P) Fa0/23(I) Fa0/24(I)
5 Po5(SD) –


Step 3: Correct Port Channel Assignments on S4.

S4

S4#config t
Enter configuration commands, one per line. End with CNTL/Z.
S4(config)#int range fa0/21 – 22
S4(config-if-range)#channel-group 5 mode active
S4(config-if-range)#


Step 4: Correct and Identify Port Channel Protocol Issue on S3

To identify the protocol issues use the command show etherchannel summary

S3#show etherchannel summary
Flags: D – down P – in port-channel
I – stand-alone s – suspended
H – Hot-standby (LACP only)
R – Layer3 S – Layer2
U – in use f – failed to allocate aggregator
u – unsuitable for bundling
w – waiting to be aggregated
d – default port

Number of channel-groups in use: 3
Number of aggregators: 3

Group Port-channel Protocol Ports
——+————-+———–+———————————————-

1 Po1(SD) PAgP Gig0/1(I) Gig0/2(I)
4 Po4(SD) PAgP Fa0/23(I) Fa0/24(I)
6 Po6(SD) PAgP Fa0/21(I) Fa0/22(I)

a. Correct protocol issues on S3

S3

S3#config t
Enter configuration commands, one per line. End with CNTL/Z.
S3(config)#int range gi0/1 – 2
S3(config-if-range)#no channel-group
S3(config-if-range)#channel-group 1 mode active
S3(config-if-range)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up

S3(config-if-range)#int range fa0/21 – 22
S3(config-if-range)#no channel-group
S3(config-if-range)#channel-group 6 mode active
S3(config-if-range)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/21, changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/21, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/22, changed state to down

S3(config-if-range)#int range fa0/23 – 24
S3(config-if-range)#no channel-group
S3(config-if-range)#channel-group 4 mode active
S3(config-if-range)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/23, changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/23, changed state to up

THE END, HAPPY YOU TO ASCERTAIN YOU  HERE

Lab file is taken from netacad.com

By Admin

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