Networking

440 readers

1 users here now

This is a community dedicated to all types of computer networking (physical/virtual/cloud/etc.)

Computers use common communication protocols over digital interconnections to communicate with each other. These interconnections are made up of telecommunication network technologies based on physically wired, optical, and wireless radio-frequency methods that may be arranged in a variety of network topologies.

Helpful Links:

Computer Network (Wikipedia)

Rules:

Posts must be relevant to networking
No NSFW content
No hate speech, bigotry, etc
Try to keep discussions on topic
No spam of tools/companies/advertisements.
It’s OK to post your own stuff part of the time, but the primary use of the community should not be self-promotion.

founded 1 year ago

MODERATORS

[email protected]

How do I whitelist a dynamically changing application sync server IP ? (programming.dev)

submitted 1 year ago by [email protected] to c/[email protected]

1 comments fedilink hide all child comments

I have a vm for which I have s specific whitelist only firewall. It is supposed to only allow connections to the IPs an app connects to when syncing.

I first got the sync server IP's listening to tcpdump, then when I had the IP's I activated the whitelist.

This worked perfectly for some time, but now it appears that the IP's have changed. I could do the same thing again but repeating the process regularly is annoying and defeats the whole purpose of only ever allowing network connections to specific whitelisted serves.

Alternatively, I could set up a process to only allow network traffic from that app somewhat.

Using debian-11 btw.

Any help is appreceated !!!

top 1 comments

sorted by: hot top controversial new old

[–] [email protected] 4 points 1 year ago

What you would have to do is setup dynamic DNS on the machines you want to whitelist (you can use duck dns or buy a domain and use cloudflare). From there, it depends how you are whitelisting and if it supports the hostname. For example, if you are using ufw, you can write a bash script that runs every few minutes that grabs the ips by resolving those hostnames and updates the entries.