From 1ef301c631b5de18427ac7c0c10db436fbd18308 Mon Sep 17 00:00:00 2001 From: Sven Dowideit Date: Mon, 17 Jul 2017 15:27:48 +1000 Subject: [PATCH] Add some docs for the new console options Signed-off-by: Sven Dowideit --- .../adding-kernel-parameters/index.md | 35 +++++++++++++++---- 1 file changed, 29 insertions(+), 6 deletions(-) diff --git a/docs/os/configuration/adding-kernel-parameters/index.md b/docs/os/configuration/adding-kernel-parameters/index.md index 35a3bcbd..a3dc3484 100644 --- a/docs/os/configuration/adding-kernel-parameters/index.md +++ b/docs/os/configuration/adding-kernel-parameters/index.md @@ -4,9 +4,11 @@ layout: os-default --- -## Kernel parameters +## Kernel boot parameters -There are two ways to edit the kernel parameters, in-place (editing the file and reboot) or during installation to disk. +RancherOS parses the Linux kernel boot cmdline to add any keys it understands to its configuration. This allows you to modify what cloud-init sources it will use on boot, to enable `rancher.debug` logging, or to almost any other configuration setting. + +There are two ways to set or modify persistent kernel parameters, in-place (editing the file and reboot) or during installation to disk. ### In-place editing @@ -14,10 +16,6 @@ To edit the kernel boot parameters of an already installed RancherOS system, use > To activate this setting, you will need to reboot. -#### Graphical boot screen - -RancherOS v1.1.0 added a syslinux boot menu, which on desktop systems can be switched to graphical mode by adding `UI vesamenu.c32` to a new line in `global.cfg` (use `sudo ros config syslinux` to edit the file). - ### During installation If you want to set the extra kernel parameters when you are [Installing RancherOS to Disk]({{site.baseurl}}/os/running-rancheros/server/install-to-disk/) please use the `--append` parameter. @@ -25,3 +23,28 @@ If you want to set the extra kernel parameters when you are [Installing RancherO ```bash $ sudo ros install -d /dev/sda --append "rancheros.autologin=tty1" ``` + +### Graphical boot screen + +RancherOS v1.1.0 added a Syslinux boot menu, which allows you to temporarily edit the boot paramters, or to select "Debug logging", "Autologin", both "Debug logging & Autologin" and "Recovery Console". + + +On desktop systems the Syslinux boot menu can be switched to graphical mode by adding `UI vesamenu.c32` to a new line in `global.cfg` (use `sudo ros config syslinux` to edit the file). + +### Useful RancherOS cloud-init or boot settings + +#### Recovery console + +`rancher.recovery=true` will start a single user `root` bash session as easily in the boot process, with no network, or persitent filesystem mounted. This can be used to fix disk problems, or to debug your system. + +#### Enable/Disable sshd + +`rancher.ssh.daemon=false` (its enabled in the os-config) can be used to start your RancherOS with no sshd daemon. This can be used to futher reduce the ports that your system is listening on. + +#### Enable debug logging + +`rancher.debug=true` will log everything to the console for debugging. + +#### Autologin console + +`rancher.autologin=` will automatically log in the sepcified console - common values are `tty1`, `ttyS0` and `ttyAMA0` - depending on your platform.