cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Announcements
Join Customer Connection to register!
13919
Views
10
Helpful
6
Replies
tato386
Frequent Contributor

replacing failed member in stackwise

The stackwise marketing info states that when a failed member is replaced with a new switch the replacement switch "gets the exact configuration of the old device".  I would figure it takes a little more than just disconnecting and connecting a new switch in the same spot on the stack.

Has anybody had any experience doing this with 3750 family switches?  What are the steps to prepare the stack for a new member?  what steps need to be taken on the replacement switch before insertion into the stack to make sure it gets configured like the unit it was replacing?

Thanks,
Diego

1 ACCEPTED SOLUTION

Accepted Solutions

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Replacing a failed switch is a combination of the procedures for removing a member switch and adding a member switch.  1st step of removing a member switch is turning it off but this is normally the case of a failed switch member, i.e. it's already off.

The important parts of inserting the replacment switch are setting its switch number to be the same as the member switch that failed and insuring it already running the same IOS version.

The combination of setting the replacement switch's switch number and IOS version is the "correct prep".

In theory, if the IOS versions were different, if the IOS supports auto upgrade, the switch might be connected into the stack without first insuring its IOS was the same version.  Also, if there's a switch number conflict, most likely the replacement switch will automatically get the failed switch's member number, but it won't change if there's no conflict.  I.e. it's possible, unless you set the member number before hand, it will join with the wrong member number.  However, you can renumber stack member numbers after the fact but will need to reload them.  Also in theory, I believe the renumber member switch, again if same model, should inherit the prior switch's port configs.  Also however, I recommend insuring the IOS and switch number before you connect the replacement.  This both to avoid possible issues and to minimize the actual time needed to actually bring the switch member on-line when you actually connect it.

If the switch is the same model, the stack should already have the failed switch's port configurations and will use that on the replacement switch.

Then you just place the replacement in the stack, powered off, connect the stack cables, as they were on the failed switch member, power it on, and it should join the stack and become what the failed switch was.

The disconnecting the failed switch member and connecting its replacement is the "it's pretty easy".

BTW, if the replacement switch is a different model, it's not that much more difficult.  In that case, you can just add the replacement and will need to configure its ports when it joins the stack.  Again, you want to insure the same IOS version and to set the switch number first.  You can also drop the provision information for the failed stack member, define the replacement stack member model and provision its ports before you add it to the stack.

View solution in original post

6 REPLIES 6
Reza Sharifi
Hall of Fame Expert

Joseph W. Doherty
Hall of Fame Expert

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

I've done it, and what you need to do is defined in the reference Reza provided.

It's pretty easy with correct prep.  The most important key is insuring the switch you are adding to replace a failed switch member matches the same type that failed.  If it doesn't you'll need to either preprovision for it or provision it after it's been added.

BTW, this is sort of like replacing a failed line card on a chassis.  If the line card is being replaced with the same type of line card vs. replacing with a different type of line card.

Joseph:

The document is very informative but doesn't specifically mention a hardware failure scenario.  It seems to only reference planned switch member replacements.

In your post you mention that the new switch should be the same model.  Got that, no problem.  But you also mention "its pretty easy with correct prep".  So other than having same model what else do I need to do to make sure I have "correct prep"?

Thanks,

Diego

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Replacing a failed switch is a combination of the procedures for removing a member switch and adding a member switch.  1st step of removing a member switch is turning it off but this is normally the case of a failed switch member, i.e. it's already off.

The important parts of inserting the replacment switch are setting its switch number to be the same as the member switch that failed and insuring it already running the same IOS version.

The combination of setting the replacement switch's switch number and IOS version is the "correct prep".

In theory, if the IOS versions were different, if the IOS supports auto upgrade, the switch might be connected into the stack without first insuring its IOS was the same version.  Also, if there's a switch number conflict, most likely the replacement switch will automatically get the failed switch's member number, but it won't change if there's no conflict.  I.e. it's possible, unless you set the member number before hand, it will join with the wrong member number.  However, you can renumber stack member numbers after the fact but will need to reload them.  Also in theory, I believe the renumber member switch, again if same model, should inherit the prior switch's port configs.  Also however, I recommend insuring the IOS and switch number before you connect the replacement.  This both to avoid possible issues and to minimize the actual time needed to actually bring the switch member on-line when you actually connect it.

If the switch is the same model, the stack should already have the failed switch's port configurations and will use that on the replacement switch.

Then you just place the replacement in the stack, powered off, connect the stack cables, as they were on the failed switch member, power it on, and it should join the stack and become what the failed switch was.

The disconnecting the failed switch member and connecting its replacement is the "it's pretty easy".

BTW, if the replacement switch is a different model, it's not that much more difficult.  In that case, you can just add the replacement and will need to configure its ports when it joins the stack.  Again, you want to insure the same IOS version and to set the switch number first.  You can also drop the provision information for the failed stack member, define the replacement stack member model and provision its ports before you add it to the stack.

View solution in original post

Thank you sir.  It does sound easy.  Will try in lab first of course.

Rgds,

Diego

jessieo
Beginner

Hello Joseph,

Thank you for the information!

Please I need to know If the procedure your describe and that contained in the document provided by Reza above applies to all the switch models in the 3000 series family.

thank you!