3750 Stack Redundancy?

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We have three 3750's in a stack, they all pretty much have one vlan spanning across them (they're access layer switches). One of our systems guys went into the closet to press the mode button, he was trying to see which switch is #1 in the stack...instead of pressing the button he held it down for a good 15 seconds which caused it to reboot. I know holding the button down for that long causes the switch to erase its configuration, but he ended up affecting all the users. The I checked the switch and the vlan we have on there was down, I had to reconfigure it (the vlan settings were there, but the svi was gone). Why would holding the button down on one switch for 10 seconds affect all 3 switches?

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Olivier ARRIGHI Fri, 05/23/2008 - 15:52
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I guess each port is controlled by the master switch, including console port and buttons.So every path leads to rome....

Remember that there is 3 physical switches but only one logical switch.The IOS running is only the one on the master switch, the others are on standby.IOS acts as it's controlling just one switch.

johgill Sat, 05/24/2008 - 06:05
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If you press the mode button for a total of 10 seconds or more in a switch configured for Express Setup, the switch configuration is deleted, and the switch reboots. The switch can then be configured like a new switch, either through the web-based Express Setup program or the CLI-based setup program.

You can disable the express setup feature with "no setup express".

Here is some more information in the TAC case collection about this function:



John Gill

Right...but if you power off a switch, even the master switch, the other switches stay up and the vlans stay up...so anybody on the other two switches doesn't get affected. Why would the vlan on the entire stack get removed with the mode button? The L3 etherchannel on the other two switches stayed so I was able to connect to the switches using the IP on the etherchannel...soon as I recreated the vlan svi everything was back to normal.


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