Comment on Internal network monitoring
non_burglar@lemmy.world 3 weeks agoHow did you monitor your vlans with suricata? I have enough trouble tuning a couple subnets, never mind tuning for correlation between 3 or 4. This assumes you have different subnets per vlan, of course.
At present I only monitor the VLAN serving the ‘computer room’ which includes the servers. It’s where all the ‘stuff’ happens so I figured I’d start with the most important. However I am in the process of learning how to SPAN (Switch Port Mirroring) where you configure your managed switch to copy traffic from specific VLAN port or all VLANs ports to a dedicated ‘monitoring port’ where a micro server is running Suricata. The mirrored traffic will retain their VLAN tags and Suricata can parse these tags.
Those are the lofty plans. LOL I’m still fiddling around with it and Suricata because you have to actually set Suricata up to be able to do that. It doesn’t right out of the box.
non_burglar@lemmy.world 3 weeks ago
I’m not sure how far down this path you’ve gone, but suricata will not automatically correlate primitives into actual alerts from different vlans without transforms, which are cpu-intensive for what they do.
You may want to pull your tap/span/mirror from a point where they converge, like internal side of network egress.
It is possible to offload the correlation to a downstream SIEM or log aggregator like Wazuh or ELK. Again, it’s something I’m currently trying to spool up on. I know it can be done, I’m just trying different things until I do get it right. I appreciate any input.
non_burglar@lemmy.world 3 weeks ago
Oh, yeah, absolutely. Suricata was created not long after snort, in the days when an ids did the gathering and the correlation.
You’re totally right, the way most people and orgs do it today is to ship ids logs to a siem for the correlation, overall easier to manage. ELK is the go-to for most, not sure about wazuh, I’ve only seen it in the homelab space, but it might work.
There is a distro (not totally open source) called SELKS, which sets up suricata, elastic and some other tooling (kibana) in a commonly-used setup. I deploy it a lot because it saves time with the non-security setup with dB’s and such. Pretty easy to point syslog to it and you can see alerts right away and start tuning.
I’m envious of your position, I learned a lot setting this stuff up.