What configuration exists in CentOS but not in Ubuntu, which shows user@hostname for remote terminal sessions?

Question

We have a standard "basic server" install of CentOS 6.7 for our servers, and Ubuntu 14.04 for our desktops.

From my Ubuntu desktop, when I ssh into a remote server (ie: ssh into a CentOS instance), my terminal tab shows user@hostname:path

However, when I ssh into a remote desktop (ie: ssh into another Ubuntu instance), my terminal tab shows my_user@my_host:path. That is, it shows the local user and local hostname and local path I was in prior to ssh'ing into the remove desktop.

I have overridden PS1 for both Ubuntu and CentOS hosts

I have a local setting for PROMPT_COMMAND, but nothing on any remote CentOS or Ubuntu host.

[local-ubuntu] $ echo $PROMPT_COMMAND
[local-ubuntu] PROMPT_COMMAND=echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD}\007"

[remote-ubuntu] $ echo $PROMPT_COMMAND
[remote-ubuntu] 

[remote-centos] $ echo $PROMPT_COMMAND
[remote-centos] 

I am running GNOME Terminal 3.6.2

[local-ubuntu] $ gnome-terminal --version
[local-ubuntu] GNOME Terminal 3.6.2

Even if I unset my local PROMPT_COMMAND, and then ssh into CentOS, I get user@hostname:path displayed in the tab, but nothing when ssh'ing into Ubuntu.

So my conclusion is that there is something which CentOS is doing to display that information in my tab which Ubuntu isn't doing.

Question:

What configuration exists in CentOS but doesn't in Ubuntu, that shows user@hostname:path for remote terminal sessions?

Answer 1

Redhat (and by extension, Centos) sets PROMPT_COMMAND with titlebar adjusting control sequences by default:

% bash -xic : 2>&1 | egrep 'PROMPT|PS'
++ PROMPT_COMMAND='printf "\033]0;%s@%s:%s\007" "${USER}" "${HOSTNAME%%.*}" "${PWD/#$HOME/~}"'
++ PS1='[\u@\h \W]\$ '
% 

This setting can be found in the /etc/bashrc file on Redhat:

% grep 007 /etc/bashrc
            PROMPT_COMMAND='printf "\033]0;%s@%s:%s\007" "${USER}" "${HOSTNAME%%.*}" "${PWD/#$HOME/~}"'
% rpm -qf /etc/bashrc
setup-2.8.14-20.el6_4.1.noarch
%

Ubuntu likely does not make any such configuration change in the global shell rc file, which is why the terminal title bar is not changed.