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New Member

2 x 2960 in teaching environment.

My configuration may sound strange but it works.

I have two 2960 24 port switches. I have enabled the Layer3 functionality in them.  I am using them for cybersecurity classes so have developed multiple configurations. I have set LAN Base to IP Routing, have enabled IP routing.

Since there are multiple configurations the general setups are: I have subnetted a Class C network to create different VLAN options, 1, 4 or 8. One or both switches act as single or multiple DHCP servers to service one or more VLANS.

I am using Hyperterm and TFTP to load tftp to start then 'reload' or power cycle the switches

In the configuration giving me the strange issue is Sw1 is a DHCP server for VLAN20 (ports 1 - 12) and 30 (ports (13 - 24). Then i have set GB2 to act as a trunking port to trunk these two vlans to Sw1 same group of ports. It works perfect when i load it from either another configuraton or express setup mode.

A second configuration is 4 DHCP servers, 2 per switch, servicing 4 VLANS 2 per switch, I.E. 20 (Sw0 ports 1 - 12) 30 (Sw0 Ports 13-24) 40 (Sw1 Ports1-12) and 50 (Sw1 Ports 13-24). GB2 is now an access port just carrying traffic. VLAN1 in all cases is the GB ports.

All configurations work perfectly except when I reload the 8 VLAN after runnning the 4 VLAN Trunked. Sw1 does not show green port leds and no traffic flows. The FA ports LEDs stay amber. The GB ports show Green. The ports do NOT show blocked, the VLANS are not disabled,  in fact the ports show active connected at 100/full.

If I reboot to Express setup and load the exact same files on Sw1 it works fine. It is ALWAYS switch 1 as i have reversed which switch is which. again the configurations work correctly when I load from express setup.

FW verison 15 3 the latest.

It is acting like the switches are not fully resetting when loading a new configuration. Power cycle does nothing, portfast does not change the behavior. It is only after I load the trunking configuration I can not get sw1 to activate its ports fully.


New Member

2 x 2960 in teaching environment.

Problem is solved. Because I was only changing the VLAN assignments on Sw1 the VLAN is held in s seperate file. VLAN.dat. I can delete that file just before i reload and the ports all come up perfect.