CoreOS quickstart

Published at Sat, 21 Jan 2017 21:28:00 UTC by soywiz

Today I have tried coreOS inside vmware player and it has been pretty easy. So now I’m ready to share the steps I have followed: # Installation ## Downloading OVA OVA file can be imported in both vmware and virtualbox: ``` curl -LO https://stable.release.core-os.net/amd64-usr/current/coreos_production_vmware_ova.ova ``` ## Creating the `config-drive` We have to created the file `user_data` with the following yaml content, changing ssh-rsa line with our own public key: ```yaml #cloud-config # include one or more SSH public keys ssh_authorized_keys: - ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDGdByTgSVHq....... coreos: etcd2: # generate a new token for each unique cluster from https://discovery.etcd.io/new?size=3 # specify the initial size of your cluster with ?size=X discovery: https://discovery.etcd.io/ advertise-client-urls: http://$private_ipv4:2379,http://$private_ipv4:4001 initial-advertise-peer-urls: http://$private_ipv4:2380 # listen on both the official ports and the legacy ports # legacy ports can be omitted if your application doesn't depend on them listen-client-urls: http://0.0.0.0:2379,http://0.0.0.0:4001 listen-peer-urls: http://$private_ipv4:2380 units: - name: etcd2.service command: start - name: fleet.service command: start ``` Now we are going to create `configdrive.iso` with the `user_data`file inside: ``` mkdir -p /tmp/new-drive/openstack/latest cp user_data /tmp/new-drive/openstack/latest/user_data mkisofs -R -V config-2 -o configdrive.iso /tmp/new-drive rm -r /tmp/new-drive ``` In the case you are using windows 10, you can open a `bash for windows`, and install `genisoimage`: ``` sudo apt-get install genisoimage ``` ## Attach the ISO as a DVD After that it is enough to attach the ISO file that we have just created to the virtual machine and start it. CoreOS will detect it and we will be able to log-in with the user `core` using our own private key. CoreOS doesn’t have a default password, so this is mandatory. ## Connecting ``` ssh core@192.168.0.15 ``` ![](/images/2018/07/coreos_vmware.png) ## Usage CoreOS has a very limited functionality included in its core. That’s ideal for performance and security. * *We have some tools available from the beginning:* docker, git, wget, curl, vi. * *But we don’t have:* nano, gcc, php, python, ruby, svn, or other tools. In order to access advanced functionality, coreOS offers the tool `/bin/toolbox` that starts a container with fedora mounting the main file system in `/media/root`. In this fedora we can install whatever we want: starting with `nano`, `gcc` or `php`. And in the case we need to access our main filesystem, we have it mounted as `/media/root`.
Hoy me ha dado por probar coreOS en un vmware player y ha sido bastante sencillito, pero voy a comentar los pasos que he seguido: ## Instalación ### Descargar OVA El archivo OVA se puede importar tanto en vmware como virtualbox: ``` curl -LO https://stable.release.core-os.net/amd64-usr/current/coreos_production_vmware_ova.ova ``` ### Creación de config-drive Creamos el archivo `user_data` con el siguiente contenido cambiando ssh-rsa por nuestra clave pública: ``` #cloud-config # include one or more SSH public keys ssh_authorized_keys: - ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDGdByTgSVHq....... coreos: etcd2: # generate a new token for each unique cluster from https://discovery.etcd.io/new?size=3 # specify the initial size of your cluster with ?size=X discovery: https://discovery.etcd.io/ advertise-client-urls: http://$private_ipv4:2379,http://$private_ipv4:4001 initial-advertise-peer-urls: http://$private_ipv4:2380 # listen on both the official ports and the legacy ports # legacy ports can be omitted if your application doesn't depend on them listen-client-urls: http://0.0.0.0:2379,http://0.0.0.0:4001 listen-peer-urls: http://$private_ipv4:2380 units: - name: etcd2.service command: start - name: fleet.service command: start ``` Creamos `configdrive.iso` con el archivo `user_data` dentro: ``` mkdir -p /tmp/new-drive/openstack/latest cp user_data /tmp/new-drive/openstack/latest/user_data mkisofs -R -V config-2 -o configdrive.iso /tmp/new-drive rm -r /tmp/new-drive ``` En el caso de usar windows 10, basta con abrir un `bash for windows` e instalar `genisoimage`: ``` sudo apt-get install genisoimage ``` ### Atachear la ISO creada como dvd Luego basta con atachear el archivo ISO que acabamos de crear a la máquina virtual y arrancarla. CoreOS lo detectará y podremos loguearnos con el usuario `core` a nuestra máquina usando nuestra clave privada. CoreOS no tiene password por defecto, así que esto es necesario. ### Conexión ``` ssh core@192.168.0.15 ``` ![](/img/coreos_vmware.png) ## Uso CoreOS tiene funcionalidad muy limitada incluída en el núcleo. Lo que es ideal para el rendimiento y la seguridad. * **Disponemos de algunas herramientas ya de base:** docker, git, wget, curl, vi. * **No tenemos:** nano, ni gcc, ni php, ni python, ni ruby, ni svn, ni similares Para poder acceder a funcionalidad avanzada coreOS ofrece la herramienta `/bin/toolbox` que lo que hace es arrancar un contenedor con un fedora montando el sistema de archivos raíz en `/media/root`. En ese fedora podemos instalar lo que queramos: desde nano, gcc, php. Y si necesitamos acceder a archivos de nuestro sistema de archivos principal, lo tenemos montado en `/media/root`.