Question

Strang activity at auth.log (POSSIBLE BREAK-IN ATTEMPT)

Hello! I found a strange activity at my var/log/auth.log Looks like somebody would like to break my account For example: Address 89.248.168.35 maps to no-reverse-dns-configured.com, but this does not map back to the address - POSSIBLE BREAK-IN ATTEMPT!

There are a lot of such records in this log. How can I solve this problem or how can I be sure that my account is protected?

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Hey there,

To mimic what @gndo mentioned, fail2ban or csf can be used to automatically block these attempts.

You can also edit your /etc/ssh/sshd_config file and change the Port line to something other than 22. For example you could change it to 2222 or 9022. After editing that file, you’d want to restart sshd with a service ssh restart. This suggestion does not increase security, but lessens the login attempts and helps to keep the logs and firewall rules cleaner.

NOTE: If you install an adaptive firewall like fail2ban or are blocking ports with your software firewall, you will want to make sure you open up access to your new SSH port.

Happy coding,

Jon Schwenn Platform Support Specialist DigitalOcean