Linux hostname with more than 15 characters

[tomtom2770]

Hey all!

I think the title is pretty self-explanatory on what I am trying to achieve. I am deploying linux machines with fog and want to set the hostname to something like my-company-pc-5.
Unfortunately, the UI only allows me to enter 15 characters. Is there a way to disable this limitation?

Many thanks,
Tom

[Tom Elliott]

@tomtom2770 Not exactly nicely.

While linux allows more than 15 character hostnames, windows does not. For this reason, the GUI was coded for Windows based machines. (Start with the most restrictive set)

https://github.com/FOGProject/fogproject/blob/dev-branch/packages/web/lib/pages/hostmanagementpage.class.php#L418 is the first part of the hostname limitation for creating new hosts.
https://github.com/FOGProject/fogproject/blob/dev-branch/packages/web/lib/pages/hostmanagementpage.class.php#L1038 is the second part for editing hosts
https://github.com/FOGProject/fogproject/blob/dev-branch/packages/web/lib/fog/host.class.php#L638 is the third part for checking if the hostname is safe. Of note, the check is a regex, which can be changed for your needs. For the length specifically edit the 15 in the {1,15} portion.

You can change these however you like, but remember that changing this will not maintain these changes when you upgrade. Also, remember making the changes will allow you create hostnames on any entry longer than 15 characters and your environment may not like this.

Also, this only impacts the UI. There are some similar checks in the inits when you are trying to register hosts through the PXE menu item.

https://github.com/FOGProject/fos/blob/master/Buildroot/board/FOG/FOS/rootfs_overlay/bin/fog.man.reg#L164 Is the file that truncates hostnames to 15 characters. You’d have to comment the whole if statement to allow registering hosts with different length names. Of course there’s not validity checking so that would be handled in the UI elements.