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when I look at the spanning tree, I see that whilst the ether channel says it is blocking, the ports I am using (which as far as I am aware shouldn't be showing in the spanning tree) are showing up and saying they are forwarding. That is entirely normal. In a spanning tree, all physical links remain linked. They need to do so since the still need to send ...


Thing works fine. But I want to create more webpage, i.e:,, so I need to create more server. The problem is Router0 has only 3 ports (interface). You can either host all those web domains on one server or connect multiple servers using switches. A switch allows a router port to attach to a whole network of hosts and to provide gateway ...


for configure DHCP snooping on cisco switch,should use the following command: no ip dhcp snooping information option


If you use the following command, your problem will be solved. no ip dhcp snooping information option for example,my configuration: sw1-f1-msh-p#show run | s snooping ip dhcp snooping vlan 201,706,3200-3272 no ip dhcp snooping information option ip dhcp snooping trust


Superloop runs off IPOE and no VLAN tagging the only thing you need to add to your config is in global config "no ip routing" this should get the bridge working correctly to verify in enable mode "show bridge" and check both interfaces are forwarding traffic over vlan1 and Ethernet0


IP addresses from are multicast addresses. They cannot be used as source address or for unicast. Unless you actually own the IP address range you might want to stick to RFC 1918 private addresses:, and


Solution: it was faulty SIP/SPA module, cisco replace hardware.


You cannot connect a layer-3 channel to a layer-2 trunk channel because the layer-3 channel can only process the native VLAN unless you create subinterfaces for it. Remember that a layer-3 interface on a switch is basically the same as a router interface. You need something like: interface Port-channel5 description Native VLAN no switchport encapsulation ...


What we tried to do in the end was creating a list of all cisco routers where we noted for every one of them: IOS Software version System Image file used FPGA Version For those routers that had a connection problem, we found similarities in the IOS version, image file and FPGA version. In the end, what the local distributor of the cisco router found out ...


It is a continuous process. It is continuous because the root bridge (or any other bridge) can fail. If root fails, new root needs to be selected, and if anyone else fails, affected part of the tree need to be recomputed again. In order to prevent cycles in the topology, while the tree converges, there is a separate mechanisms to switch ports from non ...

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