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HOSTNAME Flapping Between Port Channel 5 and 3.

One distro switch and three access switches. One Dell 2950 running Linux Red Hat is plugged into one of the access switches, a Cisco 3550 running 12.2(25) IOS. The switch port is "connected" and the server gets an IP address via DHCP. Server ping to the gateway yields one successful packet with 99% failure. On the distro the error message HOSTNAME Flapping host (mac address of the server) Between Port Channel 5 and 3. Port channel 3 runs between the distro and the 3550 the server is hanging off of and 5 is to another switch all together. No matter what switch I put a sh arp I always get a pointer to a port channel away from the switch, never the switchport the server is connected. The server guys can get the server to work wired back to back to another server but not when connected to the switch. This problem sits right on the demarc between the

  • Server Networking

Re: HOSTNAME Flapping Between Port Channel 5 and 3.

Sounds like a spanning tree issue. Leave the server unplugged and document your layer1/2 topology. Is this server dual connected?

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