SSHGuard might be a bit more popular than Ossec. We know about 1 link to it since March 2021 and only 1 link to Ossec. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
I'd take it one step further and install OSSEC as well. It can be configured to run as a local daemon and report suspicious activity, and also intervene. So if somebody is brute-forcing the login on your web page, it'll create a burst of 401s which OSSEC will detect in the logs and block the offender for X minutes/hours. Source: over 2 years ago
There are now better defensive tools (I use https://sshguard.net/); not that there are any accounts on this system that are vulnerable, but it does keep the relevant logfile from growing to astronomical size. Source: about 3 years ago
snort - Snort is a free and open source network intrusion prevention system.
Fail2ban - Intrusion prevention framework
McAfee Network Security Platform - McAfee Network Security Platform guards all your network-connected devices from zero-day and other attacks, with a cost-effective network intrusion prevention system.
RdpGuard - RdpGuard allows you to protect your Remote Desktop (RDP), POP3, FTP, SMTP, IMAP, MSSQL, MySQL, VoIP/SIP from brute-force attacks by blocking attacker's IP address. Fail2Ban for Windows.
Wazuh - Open Source Host and Endpoint Security
IPBan - Block hacking attempts on RDP, SSH, SMTP and much more