Etherchannel

[rajsingh68]

I have 4506 standard sup V.  Protocol is used HSRP . We are facing the issue to outdrop is increase at couple of port (2/5) out of 5. But there is no service impact.

There is 5 ports in etherchannel.

Please suggest

thanks

[Pawan Raut · Accepted solution]

You mean output drop? Can you share sh int output o those interafce

[rajsingh68]

we have two core switches, CS01 is connected with CS02. Protocol running is HSRP / PVST. switch details given below CS-1:- cisco WS-C4506 (MPC8245) processor (revision 4) with 524288K bytes of memory.　 Processor board ID FOX1120147U　 MPC8245 CPU at 400Mhz, Supervisor V　 Last reset from PowerUp　 32 Virtual Ethernet interfaces　 146 Gigabit Ethernet interfaces　 511K bytes of non-volatile configuration memory　 IOS :- :cat4500-entservicesk9-mz.150-2.SG8.bin　 CS-2 cisco WS-C4506 (MPC8245) processor (revision 4) with 524288K bytes of memory.　 Processor board ID FOX1120148L　 MPC8245 CPU at 400Mhz, Supervisor V　 Last reset from PowerUp　 32 Virtual Ethernet interfaces　 146 Gigabit Ethernet interfaces　 511K bytes of non-volatile configuration memory.　 IOS : cat4500-entservicesk9-mz.150-2.SG8.bin

[Mark Malone]

can you post the interface from each member of the port-channel and the port-channel interfaces as well so we can see the problem

Also post the the sh run interface of each port-channel

and --sh run | i load

[rajsingh68]

Dear Sir

Please find the output

EtherChannel Load-Balancing Configuration:
        src-dst-mac

EtherChannel Load-Balancing Addresses Used Per-Protocol:
Non-IP: Source XOR Destination MAC address
  IPv4: Source XOR Destination MAC address
  IPv6: Source XOR Destination MAC address

Age of the Port-channel   = 31d:16h:03m:12s
Logical slot/port   = 11/10          Number of ports = 5
Port state          = Port-channel Ag-Inuse
Protocol            =   LACP
Port security       = Disabled

Ports in the Port-channel:

Index   Load   Port     EC state        No of bits
------+------+------+------------------+-----------
  1     00     Gi3/20   Active             0
  0     00     Gi3/47   Active             0
  4     00     Gi4/3    Active             0
  3     00     Gi4/20   Active             0
  2     00     Gi4/48   Active             0

Time since last port bundled:    14d:22h:09m:36s    Gi4/3

[Mark Malone]

make sure your load balancing correctly with the etherchannel and not all traffic is going down one link only causing it to drop

alter it if you need to

(config)#port-channel load-balance ?
  dst-ip                      Dst IP Addr
  dst-mac                     Dst Mac Addr
  dst-mixed-ip-port           Dst IP Addr and TCP/UDP Port
  dst-port                    Dst TCP/UDP Port
  mpls                        Load Balancing for MPLS packets
  src-dst-ip                  Src XOR Dst IP Addr
  src-dst-mac                 Src XOR Dst Mac Addr
  src-dst-mixed-ip-port       Src XOR Dst IP Addr and TCP/UDP Port
  src-dst-port                Src XOR Dst TCP/UDP Port
  src-ip                      Src IP Addr
  src-mac                     Src Mac Addr
  src-mixed-ip-port           Src IP Addr and TCP/UDP Port
  src-port                    Src TCP/UDP Port
  vlan-dst-ip                 Vlan, Dst IP Addr
  vlan-dst-mixed-ip-port      Vlan, Dst IP Addr and TCP/UDP Port
  vlan-src-dst-ip             Vlan, Src XOR Dst IP Addr
  vlan-src-dst-mixed-ip-port  Vlan, Src XOR Dst IP Addr and TCP/UDP Port
  vlan-src-ip                 Vlan, Src IP Addr
  vlan-src-mixed-ip-port      Vlan, Src IP Addr and TCP/UDP Port

Aswell is there qos running on the link ?

you may be spiking queues if the buffer is filling

If you provide more information what your seeing exactly and some config in place we can help further , there is not enough information yet to suggest what the issue is

[rajsingh68]

Dear sir

we have two core switches, CS01 is connected with CS02. Protocol running is HSRP / PVST. switch details given below

CS-1:- cisco WS-C4506 (MPC8245) processor (revision 4) with 524288K bytes of memory.　

Processor board ID FOX1120147U　

MPC8245 CPU at 400Mhz, Supervisor V　

Last reset from PowerUp　

32 Virtual Ethernet interfaces　

146 Gigabit Ethernet interfaces　

511K bytes of non-volatile configuration memory　

IOS :- :cat4500-entservicesk9-mz.150-2.SG8.bin　

CS-2 cisco WS-C4506 (MPC8245) processor (revision 4) with 524288K bytes of memory.　

Processor board ID FOX1120148L　

MPC8245 CPU at 400Mhz, Supervisor V　

Last reset from PowerUp　

32 Virtual Ethernet interfaces　

146 Gigabit Ethernet interfaces　

511K bytes of non-volatile configuration memory.　

IOS : cat4500-entservicesk9-mz.150-2.SG8.bin

thanks a a lot

regqards

raj singH

09871285855

[rajsingh68]

Dear sir

Please find the details

 show config  | i load
port-channel load-balance src-dst-mac
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30
 load-interval 30

regards

raj singh

[Joseph W. Doherty · Accepted solution]

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Posting

Etherchannel port loading is impacted by the "nature" of your traffic and the load balancing algorithm being used.  Sometimes a different load balancing algorithm will better distribute your traffic.  However, even the most optimal choice doesn't avoid the situation that individual flows are going to be directed to particular ports w/o regard to actual load on those ports.  I.e. a very active/busy flow, or flows, might congest a port no matter what you do.

Also BTW, on a Sup V, I recall best load distribution might be achieved by using a power of 2 for your number of ports within an Etherchannel, i.e. your choice/usage of 5 ports will generally also contribute to unequal load distribution.