# Operating with Cold Keys One of the primary things to keep in mind about cold keys is that they are often kept on cold nodes which are not connected to a main blockchain and are offline. The primary use of cold keys is to generate a operational certificate along with the verification key and KES period. This will show the code needed to generate an operational certificate or node.cert: ``` cardano-cli shelley node issue-op-cert \ --kes-verification-key-file kes.vkey \ --cold-signing-key-file cold.skey \ --operational-certificate-issue-counter cold.counter \ --kes-period 65 \ --out-file node.cert ``` (The code used comes from ) ![](https://user-images.githubusercontent.com/73238815/134784136-067cb02b-8117-4eb0-b9a3-422a27d670e7.png) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://certified.cryptobounty.org/guides/operating-with-cold-keys.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.