IPv6 to IPv4 - is it possible?

[wioxjk]

I have not found any documentation regarding this matter, so I need to open up a ticket here in order to get some lights on my question :)

My situation:
A loadbalancing server with IPv4 and IPv6, that proxies to servers with only IPv4. Is it possible to let clients connect to pen over IPv6 and pen itself check the IPv4 servers in the backend?

[UlricE]

Certainly, you can even proxy Unix sockets. Convoluted example here:

http://morestuff.siag.nu/2014/04/14/using-pen-as-an-address-family-adapter/

Less convoluted example:

ulric@debtest:~/Git/pen$ ./pen -df ::1:2222 127.0.0.1:22
2017-08-18 22:51:59: read_cfg((null))
2017-08-18 22:51:59: Before: conns = (nil), connections_max = 0, clients = (nil), clients_max = 0
2017-08-18 22:51:59: expand_conntable(500)
2017-08-18 22:51:59: After: conns = 0x1c24900, connections_max = 500, clients = 0x7f94a8592010, clients_max = 2048
2017-08-18 22:51:59: pen 0.34.1 starting
2017-08-18 22:51:59: servers:
2017-08-18 22:51:59: 0 127.0.0.1:22:0:0:0:0

And in another window:

ulric@debtest:~$ ssh -p 2222 ::1

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
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