Udev - symlinks

For ease of server maintenace it is sometimes preferable to use a human readable symlink to a device rather than refer to the some what cryptic computer device names. For example /dev/ups is easier to understand that this device has a UPS attached to it rather than /dev/ttyS0. However any manually entered symlinks do not survive a reboot as udev creates the /dev structure at boot time.

You have to get udev to create the symlinks for you. This is straightforward with the use of a custom template.

1. Create the directory /etc/e-smith/templates-custom/etc/udev/rules.d/10-local.rules and change to it.
2. Using your favorite text editor create a file with a suitable mnemonic name with content similar to: # For <description of symlink> KERNEL="<device>", SYMLINK="<name>" Where:
   <device> is the device name. eg. ttyS0.
   <name> is the name of the symlink. eg. ups.
3. Expand the template: expand-template /etc/udev/rules.d/10-local.rules This is required as a seperate expansion as this template is not known to SME Server.

Using a template also means that only the template needs to be changed should there be an alteration to the hardware, rather than finding and editing individual application config files.