What it checks
net.ipv4.tcp_syncookies enabled.
Why it matters
Mitigates SYN-flood DoS.
How to fix
sysctl net.ipv4.tcp_syncookies=1.
InfraGuard runs all 36 checks across your servers at once and grades each host A–F.
Track these versions on your own servers
InfraGuard collects installed software versions from every server and flags the ones with known vulnerabilities. Self-hosted — nothing leaves your network.