How to get notified when SFTP Remote Server is UP using Spring Boot Java?

Question

I am working on a scenario, where the SFTP remote server is down for an hour or more. How do I get notified when the remote server is up again so that I can SFTP files as soon as it is back to an active state. Currently, I am using Spring integration sftp, and spring-boot java f/w. Are there any built-in methods I can use?

Answer 1

I'm not sure if such a question is correct at all: the SFTP server ia passive service: you call it, no opposite. Therefore I doubt there is such a feature in any SFTP vendors like send notifications about its lifecycle.

You can ping the server periodically with a DefaultSftpSessionFactory.getSession() . It checks for the connection and tries to reconnect otherwise.

Another solution is to use a RequestHandlerRetryAdvice on your SftpMessageHandler to retry sending the file for some number of attempts with some backoff in between.

See more in docs: https://docs.spring.io/spring-integration/docs/current/reference/html/messaging-endpoints.html#retry-advice