openssh unix dev - Aug 2019 - access remote host aliases with proxyjump

Hi,

I think it would be a good idea to allow the use of remote host aliases 
when using ProxyJump (or maybe it's already doable and there's something
I don't get ?)

On my laptop I have the following config, which works fine :

Host bastion
 ?????? Hostname bast.example.net
 ?????? User john

Host somehost
 ?????? ProxyJump bastion
 ?????? Hostname yellowstone.example.local
 ?????? Port 15200
 ?????? User john


Now, on bastion I have already defined the following alias :

Host somealias
 ?????? Hostname yellowstone.example.local
 ?????? Port 15200
 ?????? User john


So, I thought on my local machine I could just do :

Host somehost
 ?????? ProxyJump bastion
 ?????? Hostname somealias

But it doesn't work :

channel 0: open failed: administratively prohibited: open failed
stdio forwarding failed
ssh_exchange_identification: Connection closed by remote host


So, if I get it right when using ProxyJump you have to define the whole 
connection infos of the final target, even though it's already defined 
on the bastion. Any idea how to take advantage of the ?? somealias ?? 
alias defined on the bastion ?

Thanks

On Tue, 6 Aug 2019, Chentao Credungtao wrote:
> Hi,
> 
> I think it would be a good idea to allow the use of remote host aliases
when
> using ProxyJump (or maybe it's already doable and there's something
I don't
> get ?)
It's definitely possible and your configuration is very close to working.
> On my laptop I have the following config, which works fine :
> 
> Host bastion
>     Hostname bast.example.net
>     User john
> 
> Host somehost
>     ProxyJump bastion
>     Hostname yellowstone.example.local
>     Port 15200
>     User john
> 
> 
> Now, on bastion I have already defined the following alias :
This is where you went wrong. Put this block on your laptop - the
configuration on the jump host is never evaluated, basically all
the action happens on the initiating host.
> Host somealias
>     Hostname yellowstone.example.local
>     Port 15200
>     User john