Re: Couple Minor “Bugs” (?)

[Ole Tange]

On Fri, Jun 10, 2022 at 12:54 AM Larry Ploetz <lploetz.sg@gmail.com> wrote:

> I'm trying to use ssh's proxy (-J flag) with GNU parallel. The -J flag on ssh 
> allows multiple hosts to be specified with commas between them.

You clearly already know the , is the culprit.

> larryp-MBP:~ larry$ seq 48 | parallel -j0 --sshlogin '24/ssh 
> -JINTHOST1,INHOST2 TARGETHOST' echo {}

I am not sure how this should be solved. --sshlogin allows you to
specify multiple sshlogins separated by comma:

    parallel --sshlogin host1,host2

or:

    parallel --sshlogin "myssh host1,myssh host2"

or:

   parallel --sshlogin "24/ssh host1,16/ssh host2"

So the problem here is that comma is used in the ssh command.

> Also, in attempting to get around that limitation:
>
> larryp-MBP:~ larry$ seq 48 | parallel -j0 --sshlogin '24/ssh 
> -JINTHOST1\,INTHOST2 TARGETHOST' echo {}

And currently GNU Parallel does not support that: It splits on , even
if preceded by \ . But this might be a reasonable solution - it is
definitely doable. Though I cannot recall ever seeing a situation in
which you use \,

Currently you can workaround this by using ~/.ssh/config: here you can
put in ProxyJump for TARGETHOST.

Or if the JumpHosts are the same for all servers:

  parallel --ssh 'ssh -JINTHOST1,INTHOST2' --sshlogin 24/TARGETHOST

To everyone else: What do you think? Is \, the right solution here?
Would ,, be better (it might be less intuitive but cause less quoting
stress)?


/Ole