🚰 Docker connection reset during builds

Recently while trying to deploy a test docker container on my homelab's docker instance, I kept running into an error similar to this one

Caused by: java.net.SocketException: Connection reset
 at java.net.SocketInputStream.read(SocketInputStream.java:210)
 at java.net.SocketInputStream.read(SocketInputStream.java:141)
 at sun.security.ssl.InputRecord.readFully(InputRecord.java:465)

After a bunch of digging, I ran into this medium article; https://medium.com/swlh/fix-a-random-network-connection-reset-issue-in-docker-kubernetes-5c57a11de170

It summarized it's findings pretty well and walked through the whole discovery process. Something I appreciate.

Ultimately for it, it boiled down to running these commands to backup, flush, and reset iptables

# Keep a backup of the current rules incase we have to go back
iptables-save > /root/firewall.rules

# Flush all the current rules
iptables -F
iptables -X
iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT

# Confirm the rules are now empty
iptables -L

Then I had to restart docker with service docker restart for docker to reset it's own iptable rules. But from then on, no more connection reset issues.

In the event you need to roll back, you can use

iptables-resoter < /root/firewall.rules

Now get back to building something awesome!