Support Center

Contact Us

IP address change warning when using SFTP

Because our instances run in an autoscaling cluster, and we run multiple instances for high-availability, the IP addresses you connect to can be different each connection.

This causes ssh to report the IP address has been modified and requires you to update your known_hosts file to delete and re-add a new host key against a new IP address.

The problem can be resolved by using the SSH option CheckHostIP set to no:

sftp -o CheckHostIP=no 'serviceid\'

This will ignore any IP future IP checks and resolve this issue.

Importantly - the IP address may change, but the host key fingerprint will never change:

2048 SHA256:vgxrsQY4LuABBPrAIdBHQSF+UQgF5PuWzsqtLYSAua4 (RSA)
2048 MD5:f3:d6:0d:1d:a0:98:33:4f:b5:ef:f3:0d:e5:e5:e4:9f (RSA)