Selected for slot leader but failed to mint new block

Hi Alex I have taken a look on the other forum post but havent been able to find a solution.

Moving the files over did not solve the problem either unfortunately.

:frowning: Same errors in logs?

Hi Alex,

I missed the logs for the previous block to see the error msg. We are elected as a slot leader today so I will check logs then and update this thread.

I have in the meantime rotated the keys again to see if that helps.

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It seems the issue was fixed?

Yes! Thank you so much for your help.
Rotated the keys again and copied kes.vkey plus op.cert over and that seemed to do it. Also noticed this morning one of my relay nodes time was out of sync. So that could also have fixed the issue

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I rotated the KES on 4 of july and last night guess what… I lost 2 blocks; I rotated again the KEYS this morning and waiting for the next block… meantime I opened a case to IOHK

Hmm seems to be a recurring issue, I noticed the error mentions the counter.

This post you sent me mentions the current counter being smaller than the previous counter. I think you might have encountered the same problem?

gLiveView can only tell you what your current KES key’s start/expiry time is. But another base property of KES key is the number of times your key was rotated. You can check your current key using cardano-cli text-view decode-cbor --in-file <path>/op.cert | grep int | head -1 . Your current cert can only be higher, (not lower) than the one used for your previous blocks. The upcoming public pgrest API on guild-operators website (currently in alpha stage) will allow you to query your last created block’s OCert number for validation too.

PS: You can rotate multiple times to a higher counter (so for example, you can go rotate until counter is 10) just fine, as it will still be higher than your previous block’s OCert counter.

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for sure is the same error, but why? and how should I know how many times I need to rotate in order to have a higher counter than last one?

Exactly… please keep me updated.
Thanks Alex

that could be the answer

I rotated few more time the KEYS and now I have the counter = 4 which should be bigger


For us I see 01. We had rotated the KES key first time last month. Is it a problem? don’t know what was the value counter value when we created the pool.
01 # int (1)

Should be fine, Still waiting for an answer from IOHK

For me it’s fine now

New block! :fire:

:hammer_and_wrench: Blocks this epoch: 1

:brick: Total blocks: 87


I read again this thread. Just to make sure
if I do this in my cold machine

cardano-cli node issue-op-cert \--kes-verification-key-file kes.vkey \--cold-signing-key-file cold.skey \--operational-certificate-issue-counter cold.counter \--kes-period 270 \--out-file node.cert

Just to make sure again which file should I bring to my BP
only node.cert or also the cold.counter ?


my result:

09 # int(9)

So, should I create the node.cert then copy to the BP then see if the result should be 10 ?

I create node.cert → copy to BP → restart node → the result is
01 # int(1)

Do it again
02 # int(2)

Do it again
03 # int(3)

Am I cool now?

I think the common issue here is that each time you use your cold environment you need to use the same counter file which is modified each time you run the cardano-cli node issue-op-cert command. If you don’t use the increased node.counter your block production will fail because your new certificate will have the same counter than the old one…
This might also happen if your counter file is write protected and fails to be updated (but I think there is an error message when that is the case)

A good habit is to always keep your previous keys and certificate at each rotation so that you can verify this counter…


Exactly :+1: but I had mo clue before to happen

Hi Alex, reading the post, it seems that the problem was the relay time out of sync, would you agree?

I also followed the coincashew guide to rotate keys and have backups of all the files previous to the rotation, if I cat node.counter files, I get “description”:“Next certificate issue number: 1” from the backup and “description”:“Next certificate issue number: 2” from the new counter, I hope my KES are alright. I can confirm that the kes.vkey didn´t change with the cardano-cli node issue-op-cert command.

I’m a little nervous because my pooll is elected for its first block today, it’ll be a tragedy if we missed it.

How do you check if the node times are sync?

So, Am I already doing the right thing? I only get 1 block this epoch. So, it is only one shot. Can somebody confirm that I already do it right?
Thank you.

Should be fine… did u minted the block?

I don’t have a full explanation about this issue, but I think u are fine
Before to hapen to me I didn’t knew about this behavior and I rotated keys n times and also I minted blocks before

Not yet, my schedule is in couple of days again. I’ll let you know if everything is alright.
Thank you.