👀 Views: 2 💬 Answers: 1 📅 Created: 2025-06-01

docker centos networking bash

I'm having a hard time understanding I can't seem to get I'm encountering unexpected behavior with network isolation in Docker containers running on CentOS 8. Specifically, I have set up a Docker container that should be operating in its own network namespace, but it seems to be able to access the host's network unexpectedly. I used the following command to run my container: ```bash docker run --rm -it --network bridge my-container-image ``` However, when I try to ping the host from within the container, it succeeds: ```bash ping -c 4 <host_ip_address> ``` This should not be possible if the container is properly isolated. I've checked the Docker configuration and confirmed that the default bridge network is being used, as shown in my Docker network list: ```bash docker network ls ``` Output: ``` NETWORK ID NAME DRIVER SCOPE abc123456789 bridge bridge local ``` To troubleshoot further, I created a custom bridge network: ```bash docker network create my-custom-network ``` And then ran my container with: ```bash docker run --rm -it --network my-custom-network my-container-image ``` Yet, I noticed the same issue persists. I also checked that I don't have any additional iptables rules allowing access from the container to the host, and the output of `iptables -L` shows no custom rules that would permit such traffic. As a workaround, I've tried adding a `--cap-drop=ALL` flag to my Docker run command to drop all capabilities, but it didn't help. I'm currently running Docker version 20.10.7 on CentOS 8 with Kernel version 4.18.0-240.el8.x86_64. Can anyone explain why the network isolation isn’t working as expected? Could there be a misconfiguration in my Docker settings, or is this a known issue with the current version? For context: I'm using Bash on Ubuntu 20.04. I'd be grateful for any help. My team is using Bash for this mobile app. I recently upgraded to Bash 3.10. Any suggestions would be helpful.