Forward local port or socket file to remote socket file

Question

Quick question - I run two linux boxes, one my own desktop and the other my VPS. For security reasons on the VPS end I opted for socket connections to MySQL (/var/run/mysqld/mysql.sock). I know I can tunnel like this: ssh -L 3307:127.0.0.1:3306 user@site.com if I set up the remote sql server to listen on some port, but what I want to know is can I do something like: ssh -L /path/to/myremotesqlserver.sock:/var/run/mysqld/mysql.sock thereby tunnelling two sockets, as opposed to two ports?

A perfectly acceptable solution would also be to forward a local port to the remote socket file, but where possible I'm trying not to have tcp servers running on the remote box.

(and yes, I know tcp would be easier).

Thanks all,

Nf.

Answer 1

No, you cannot. At least, I cannot plausibly think of a method to use the MySQL socket file remotely. Your only options involve TCP/IP sockets or running a client local to the server either via SSH or something like phpMyAdmin.

Answer 2

i haven't done this, but i would try with socat. maybe something like:

ssh xxx@yyy.zzz -L 9999:localhost:9999 "socat TCP-LISTEN:localhost:9999 UNIX-CONNECT:/var/run/mysqld/mysql.sock"
socat UNIX-LISTEN:/path/to/local/socket TCP:localhost:9999

again, i have never done anything like this.

Answer 3

Forward a local socket on demand

• Setup SSH public key authentication
• Install socat at both ends
• create a directory locally for your sockets, inaccessible to other users.

export SOCKET_DIR=~/.remote-sockets
socat "UNIX-LISTEN:$SOCKET_DIR/mysqld.sock,reuseaddr,fork" \
EXEC:'ssh user@server socat STDIO UNIX-CONNECT\:/var/run/mysqld/mysqld.sock'

then

mysql -S $SOCKET_DIR/mysqld.sock -u mysqluser -p

stolen from forwarding unix domain sockets with ssh and socat