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Cisco 3850 switch, if IOS boot fails at startup does it boot up to other ios

Hello,

I have 3850 stackable switches and reboot them to load into the new IOS, but say the IOS fails to boot to the new IOS does it automatically boot from previous IOS or do I have to go rommon mode?

8 Replies 8

Collin Clark
VIP Alumni
VIP Alumni

Have you set the boot statement?

boot system flash:/ios_file.name

Yes I did, is there a way to configured  the switch to boot from the second IOS incase the first IOS doesn't boot up or will it do it automatically?

It will do that automatically. If you type 'show run | i boot' does it show only the new IOS image or both?

It doesn't show anything, do I need to configure with the boot system flash:/ios_file.name command?

try 

show bootvar  or

sh boot system
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable does not exist

Boot Variables on next reload:
BOOT variable = flash:packages.conf
Allow Dev Key = yes
Manual Boot = no
Enable Break = no

Above is from one of my 3850




>> Marcar como útil o contestado, si la respuesta resolvió la duda, esto ayuda a futuras consultas de otros miembros de la comunidad. <<

If you have more than IOS image in flash then you need to specify which one to boot. If it fails to load that image it will search flash for another image and try and boot with that. You only need the one boot statement.

It doesn't have the boot system flash command configured. do I have to configure the boot flash command twice such as do the boot flash: ios1 and then boot flash:ios2 for the switch to automatically load to ios2 in case ios1 doesn't work or do I need to configure only once boot flash: ios1 no need for boot flash:ios2?

Thanks,

Hi

Sometimes you need to remove the old boot system flash and then configure the new one:

no boot system flash:/ios_file.name

boot system flash:/ios_file.name

then

write 

to save the changes. 




>> Marcar como útil o contestado, si la respuesta resolvió la duda, esto ayuda a futuras consultas de otros miembros de la comunidad. <<
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