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- Hundreds of failed ssh logins 15 answers
I have a web application that I'm hosting on an Amazon Ubuntu server, and it has a public IP address - and very little traffic.
I was observing the authorization logs in /var/log, and noticed several like the following, typically 15-30 times/day, and all with a different username.
Sep 9 01:15:37 ip-xx-xxx-xx-xxx sshd: Invalid user zabbix from 18.104.22.168<br> Sep 9 01:15:37 ip-xx-xxx-xx-xxx sshd: input_userauth_request: invalid user zabbix [preauth]<br> Sep 9 01:15:37 ip-xx-xxx-xx-xxx sshd: Received disconnect from 22.214.171.124: 11: Bye Bye [preauth]
Most of these come from Vietnam and China. I assume this is typical, that somebody has programmed a bot to trawl the web and attempt logins. There are similar threads about understanding logs, but my question is this:
Is this volume normal, and how do I establish a baseline for normal activity levels?
If I'm assured about security - and I am, I use locally saved SSH keys - is there any harm to these failed requests, even as they grow in number over time?