Mac computer name (acer-xxxxxxxxxx)?

My Mac name on networks have changed! I don't know how this happened, I just want to change it back. The name used to be something like 'tyilos-macbook', but now it's called 'acer-6bfc9f1844'.

Screenshots:

As I understand it, terminals will show your hostname and it will only be the same as your local computer name when it has not be given a specific hostname and it can not find an answer from both the DHCP Server or by using a reverse lookup against your DNS server.

So, it would be best to start looking at both your dhcp server and your dns server to see if either(or both) has an stale entry against your ip address.

Alternatively, you can override your hostname by setting it in your /etc/hostconfig by adding a line like

HOSTNAME=xxxx

To edit the file, you can use SUDO pico /etc/hostconfig