hostsetup

Requirementts

• docker 26.0.0
• golang 1.22.4

About

The utility allows you to set the host name in Linux and change the list of DNS servers.

Changing such settings on the system may be unsafe, so the service is launched in a docker container. Only one process can be started in a container (systemd cannot be started), so methods are used that last until the system is rebooted.

Docs

You can use the following commands:

• set-hostname <name> - set the host name
• list-dns-servers - show the list of DNS servers
• add-dns-server <dns-server> - add a DNS server
• delete-dns-server <dns-server> - delete the DNS server.

Build

Service

You can build the service a project manually with docker. You have to build an image and run a containers with commands:

docker build \
	-t hostsetup-base:1.0 \
	-f docker/base.build.Dockerfile \
	.

docker run \
	--rm \
	-p 8080:8080 \
	-v .:/workspace/hostsetup \
	--env-file=hs.env \
	--cap-add SYS_ADMIN \
	hostsetup-base:1.0 \
	go run /workspace/hostsetup/cmd/service/main.go

Or using:

make build-images
make run-base

Adding capability (--cap-add) is not a good practice, but due to the lack of alternatives it is a valid solution.

Run

Before starting, be sure to make sure that the ports in the launched command and the env file match.

You can run existing dockerized application with commands:

docker build \
	-t hostsetup-base:1.0 \
	-f docker/base.build.Dockerfile \
	.

docker build \
	-t hostsetup:1.0 \
	-f docker/hostsetup.Dockerfile \
	.

docker run \
	--rm \
	-p 8081:8081 \
	--env-file=hs.env \
	--cap-add SYS_ADMIN \
	hostsetup:1.0

Or using:

make build-images
make run-service

Using

You can run the command by running the main-file, for example:

go run cmd/client/main.go list-dns-servers

Also you can build a binary file and access it:

go build -o ./hostsetup ./cmd/client
./hostsetup set-hostname fedora1

If you need RESTful API, run gRPC-gateway (by default it runs on port 8083) with command:

go run ./gateway/gateway.go

It is important to note that the cli application has the --server flag, in which you can specify the address at which the service runs (by default port is 8081). Example:

./hostsetup add-dns-server 8.8.8.8 --server 0.0.0.0:8085

If you need help run:

./hostsetup --help