How could a jail learn which is its parent host?

[Alexey V. Degtyarev]

On 10:37 Tue 02 Mar, Panagiotis Christias wrote:

> I am looking for a simple way so each jail could know at any time in
> which (physical) server is hosted. Any suggestions?

You may push a kernel environment on physical server so it will be
available from within jail. To achieve it, on the mainhost (physical
server) add to /boot/loader.conf:

x.mainhost="physical.example.com"

after reboot the mainhost server, you can use x.mainhost env from within
jail (and mainhost as well):

[root at jail1 ~]# kenv x.mainhost
physical.example.com

Check kenv(1) and loader.conf(5) for details.

-- 
Alexey V. Degtyarev