zlacker

>>todsac+(OP)
Docker has a known security issue with port exposure in that it punches holes through the firewall without asking your permission, see https://github.com/moby/moby/issues/4737

I usually expose ports like `127.0.0.1:1234:1234` instead of `1234:1234`. As far as I understand, it still punches holes this way but to access the container, an attacker would need to get a packet routed to the host with a spoofed IP SRC set to `127.0.0.1`. All other solutions that are better seem to be much more involved.

>>smarx0+P4
I wonder how many people realize you can use the whole 127.0.0.0/8 address space, not just 127.0.0.1. I usually use a random address in that space for all of a specific project's services that need to be exposed, like 127.1.2.3:3000 for web and 127.1.2.3:5432 for postgres.

>>veyh+qh
Also, many people don’t remember that those zeros in between numbers in IPs can be slashed, so pinging 127.1 works fine. This is also the reason why my home network is a 10.0.0.0/24—don’t need the bigger address space, but reaching devices at 10.1 sure is convenient!