Docker Tips - Revision history

Jeff.Krug: /* Docker DNS Failure */

2022-07-21T22:06:28Z

Docker DNS Failure

← Older revision		Revision as of 22:06, 21 July 2022
Line 23:		Line 23:
	- 192.168.10.5		- 192.168.10.5
	- 192.168.10.15		- 192.168.10.15

			It actually looks like when/if DNS fails that restarting the docker daemon without rebooting works, and in the case of Texas DPS, it appears DNS never works after a reboot, but restarting the docker daemon seems to work.

	== Random System Errors ==		== Random System Errors ==
	On Linux servers there are lots of different docker versions available via different packages. It is very easy to end up with a version that is prone to bugs. Make every effort to run a docker-ce version released by [https://docs.docker.com/get-docker/ docker] as opposed to a version in a package maintained by others.		On Linux servers there are lots of different docker versions available via different packages. It is very easy to end up with a version that is prone to bugs. Make every effort to run a docker-ce version released by [https://docs.docker.com/get-docker/ docker] as opposed to a version in a package maintained by others.

Jeff.Krug at 20:36, 11 February 2022

2022-02-11T20:36:44Z

← Older revision		Revision as of 20:36, 11 February 2022
Line 23:		Line 23:
	- 192.168.10.5		- 192.168.10.5
	- 192.168.10.15		- 192.168.10.15

			== Random System Errors ==
			On Linux servers there are lots of different docker versions available via different packages. It is very easy to end up with a version that is prone to bugs. Make every effort to run a docker-ce version released by [https://docs.docker.com/get-docker/ docker] as opposed to a version in a package maintained by others.

Jeff.Krug at 20:34, 11 February 2022

2022-02-11T20:34:20Z

← Older revision		Revision as of 20:34, 11 February 2022
Line 16:		Line 16:
	Typically the above would require a reboot or at least a complete restart of docker.		Typically the above would require a reboot or at least a complete restart of docker.

	Note that you can also add dns to the docker-compose file, just add a section with all DNS servers listed by IP address:		Note that you can also add dns to the docker-compose file, just add a section with all DNS servers listed by IP address (this may be a good best practice, but it also seems like it reduces portability of a configuration):

	dns:		dns:

Jeff.Krug: /* Docker DNS Failure */

2022-02-11T20:33:22Z

Docker DNS Failure

← Older revision		Revision as of 20:33, 11 February 2022
Line 14:		Line 14:
	}		}

	Typically the above would require a reboot or at least a complete restart of docker.		Typically the above would require a reboot or at least a complete restart of docker.

			Note that you can also add dns to the docker-compose file, just add a section with all DNS servers listed by IP address:

			dns:
			- 192.168.3.7
			- 192.168.111.1
			- 192.168.10.5
			- 192.168.10.15

Jeff.Krug: /* Docker DNS Failure */

2022-02-04T01:09:44Z

Docker DNS Failure

← Older revision		Revision as of 01:09, 4 February 2022
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	== Docker DNS Failure ==		== Docker DNS Failure ==
	It appears that sometimes docker containers can lose the ability to resolve domain names. We haven't identified an exact cause for this or even for certain if the following is a consistent fix for it, but it is worth trying. Hardcode DNS server information in the docker config file ''daemon.json'' located in ''/etc/docker''. You would replace ''#.#.#.#'' with the IP address of your local DNS server.		It appears that sometimes docker containers can lose the ability to resolve domain names. We haven't identified an exact cause for this or even for certain if the following is a consistent fix for it, but it is worth trying. Hardcode DNS server information in the docker config file ''daemon.json'' located in ''/etc/docker''. You would replace ''#.#.#.#'' with the IP address of your local DNS server:

	{		{

Jeff.Krug at 01:08, 4 February 2022

2022-02-04T01:08:52Z

← Older revision		Revision as of 01:08, 4 February 2022
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	~~Hardcode DNS server~~ in ~~docker daemon~~.~~json~~		== Intro ==
			This just has a handful of frequently encountered issues we have had with docker deploys that are worth noting in case they happen to others.

	~~Edit /etc/~~docker~~/daemon.json~~		== Docker Storage ==
			Sometimes Docker doesn't seem to release file system records correctly and can fill an entire file system, but a simple reboot of the computer may fix things. Possible it may be necessary to do execute the following command:

			docker system prune

			== Docker DNS Failure ==
			It appears that sometimes docker containers can lose the ability to resolve domain names. We haven't identified an exact cause for this or even for certain if the following is a consistent fix for it, but it is worth trying. Hardcode DNS server information in the docker config file ''daemon.json'' located in ''/etc/docker''. You would replace ''#.#.#.#'' with the IP address of your local DNS server.

	{		{
	"dns": ["10.1.2.3", "8.8.8.8"]		"dns": ["#.#.#.#", "8.8.8.8"]
	}		}

			Typically the above would require a reboot or at least a complete restart of docker.


	~~Restart~~ the ~~docker daemon for those changes to take effect:~~
	~~sudo systemctl~~ restart docker



	~~Now when you run/start a container, docker will populate /etc/resolv.conf with the values from daemon~~.~~json~~

Jeff.Krug: Created page with "Hardcode DNS server in docker daemon.json Edit /etc/docker/daemon.json { "dns": ["10.1.2.3", "8.8.8.8"] } Restart the docker daemon for those changes to take..."

2022-02-03T21:42:36Z

Created page with "Hardcode DNS server in docker daemon.json Edit /etc/docker/daemon.json { "dns": ["10.1.2.3", "8.8.8.8"] } Restart the docker daemon for those changes to take..."

New page

Hardcode DNS server in docker daemon.json

Edit /etc/docker/daemon.json

{
"dns": ["10.1.2.3", "8.8.8.8"]
}

Restart the docker daemon for those changes to take effect:
sudo systemctl restart docker

Now when you run/start a container, docker will populate /etc/resolv.conf with the values from daemon.json