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jtsokanisFlag for United States of America

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Cisco 4500 vlan configuration on fastethernet ports

We have
CiscoA 4500 with vlan1,vlan5 and a vlan6. Server room.
CiscoB 4500 with vlan5 configured. Connected to CiscoC 6513 with fiber.
CiscoC 6513 with vlan5 configured. Floor (connected with optical fiber  from server room).
CiscoD 4500 with vlan5 configured. Floor (connected with optical fiber  from server room).

The clients connected to this switches need to download a software, clients connected to ciscoc download faster, then ciscoB, and clients from ciscoD are very slow to download. Fastethernet ports are configured the same in every switch:
switchport access vlan5
switchport  mode access.

Is anything that I can add on ciscoD , to do clients faster to download. What can i change.

Thanks in advance
Avatar of bedind
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Where is the software downloading from?
Do you have a network map that shows what each switch is connected to and how the traffic is routed?
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So the performance differential between devices connected to these various switches is discernible and predictable?  Have you made any attempt to quantify the degradation?  Is D 3 times as slow, or ...?  What does the CPU utilization look like on D?  Without knowing more, my best guess (only a guess) would be that you may be suffering as the result of a broadcast storm.

This could be exacerbated by the number of ports configured for VLAN5; how do they break out by switch?  Any chance that a loop has been created in the switching fabric?  If you have any legacy network hardware or consumer grade mini switches, it may be worthwhile to revisit their function.  There are several ways that your STP config could be defeated, but any could cause significant pain.  Good luck!
Can you provide the network diagram..and the related configs..

I assume the software that is being downloaded is from your local server.

verify the path taken to the server. verify the ping response.

We had the similar issue when we were extending the switch from datacenter to the floor.
Phones were not able to download the software and we found out that the distance between the switches was the root-cause. We placed a switch in between and issue got resolved.
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Degradation is like 4 times slow. Here are configuration files. Thanks in advance
Sorry  got stuck with some issue in office. I will check and get back to you as soon as possible.
I have gone through the configurations..
Can you provide the server IP address from where the clients download the software?
Also I am not able to see the trunk configured between the switches.
no Vlan 5 on switch B..
Avatar of agonza07
Looks like you have some flapping.

1w4d: %C4K_EBM-4-HOSTFLAPPING: Host 00:E0:4C:03:9F:00 in vlan 5 is flapping between port Gi2/13 and port Gi2/47
1w4d: %C4K_EBM-4-HOSTFLAPPING: Host 00:E0:4C:03:9F:00 in vlan 5 is flapping between port Gi2/13 and port Gi2/47
1w4d: %C4K_EBM-4-HOSTFLAPPING: Host 00:E0:4C:03:9F:00 in vlan 5 is flapping between port Gi2/47 and port Gi2/13
servers have address, , dns & dhcp, we have a gateway
Yes we have wrong configuration on txt, i attached the correct one.

If we have a switch with one port configured with ‘channel group 15’ and we want to link that port to another switch, does the port on the other switch needs to be configured with the same ‘channel group 15’ as well?

do we need to add ip route or ip default-gateway?

I dont see any IPs (, , dns & dhcp in the configuration file you have sent.

Cisco says The same channel group number should be used on both ends of a PortChannel.

HOSTFLAPPING: Host 00:E0:4C:03:9F:00 in vlan 5 is flapping between port Gi2/13 and port Gi2/47
There might be Nick card teaming on the server causing the flap?
EtherChannel Feature Configuration Guidelines and Restrictions

When EtherChannel interfaces are configured improperly, they are disabled automatically to avoid network loops and other problems. To avoid configuration problems, observe these guidelines and restrictions:

•All Ethernet LAN ports on all modules, including those on a redundant supervisor engine, support EtherChannels (maximum of eight LAN ports) with no requirement that the LAN ports be physically contiguous or on the same module.

•Configure all LAN ports in an EtherChannel to use the same EtherChannel protocol; you cannot run two EtherChannel protocols in one EtherChannel.

•Configure all LAN ports in an EtherChannel to operate at the same speed and in the same duplex mode.

•LACP does not support half-duplex. Half-duplex ports in an LACP EtherChannel are put in the suspended state.

•Enable all LAN ports in an EtherChannel. If you shut down a LAN port in an EtherChannel, it is treated as a link failure and its traffic is transferred to one of the remaining ports in the EtherChannel.

•An EtherChannel will not form if one of the LAN ports is a Switched Port Analyzer (SPAN) destination port.

•For Layer 3 EtherChannels, assign Layer 3 addresses to the port channel logical interface, not to the LAN ports in the channel.

•For Layer 2 EtherChannels:

–Assign all LAN ports in the EtherChannel to the same VLAN or configure them as trunks.

–If you configure an EtherChannel from trunking LAN ports, verify that the trunking mode is the same on all the trunks. LAN ports in an EtherChannel with different trunk modes can operate unpredictably.

–An EtherChannel supports the same allowed range of VLANs on all the LAN ports in a trunking Layer 2 EtherChannel. If the allowed range of VLANs is not the same, the LAN ports do not form an EtherChannel.

–LAN ports with different STP port path costs can form an EtherChannel as long they are compatibly configured with each other. If you set different STP port path costs, the LAN ports are not incompatible for the formation of an EtherChannel.

–An EtherChannel will not form if protocol filtering is set differently on the LAN ports.

–Configure static MAC addresses on the EtherChannel only and not on physical member ports of the EtherChannel.

•After you configure an EtherChannel, the configuration that you apply to the port channel interface affects the EtherChannel. The configuration that you apply to the LAN ports affects only the LAN port where you apply the configuration.

•With Release 12.1(12c)E1 and later releases, when QoS is enabled, enter the no mls qos channel-consistency port-channel interface command to support EtherChannels that have ports with and without strict-priority queues.

•With Release 12.1(12c)E1 and later releases, to disable QoS capability checks or QoS port attribute checks in cross-module EtherChannels , enter the no mls qos channel-consistency command.
I don't have the IPs of the download servers or dns server on the configuration, do I need to have it?,  how can I define the download server onthe configuration?
Basically you dont need to have it on the switches as you have configured layer2 etherchannel.

For only VLAN5 on switches below configuration is enough for host communication.
1) EtherChannel between switches.
2) Config ether channel to pass VLAN5.
3) Config "ip routing" on the switches to enable layer3 communication.
4) The switchports connecting hosts should be in VLAN5

Thats will be able to ping from one host to host on another switch.
(pings wont be successful from switch)

For multiple VLAN to communicate between switches
1) Config Ether channel with trunking.
2) or you can configure Multiple etherchannel for each VLANs. (ex:one etherchannel for VLAN5 and another for VLAN6)
Thanks , let me check about the etherchannel and let you know how it works.
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We review etherchannels and removed gateways. Time of download is better now.
Well...happy to help :)