This script will generate a recursive, unified diff between the same path on two remote servers. You set the CONNECT1 and CONNECT2 variables as necessary to point to your hosts/paths. Of course, the users you connect as must have read access to the files/directories you’re accessing.

#!/bin/bash

# USAGE: ./sshdiff DIRECTORY
#
# E.g. ./sshdiff static/css
# Generates a recursive diff between /var/www/css/static/css
# on two separate servers.

TEMP1=~/.tmp_site1
TEMP2=~/.tmp_site2

CONNECT1="user1@hostname1:/var/www/$1"
PORT1=22
CONNECT2="user2@hostname2:/var/www/$1"
PORT2=22

mkdir "$TEMP1"
mkdir "$TEMP2"
scp -rq -P "$PORT1" "$CONNECT1" "$TEMP1"
scp -rq -P "$PORT2" "$CONNECT2" "$TEMP2"
echo -e "\n\n\n\n\n"
clear
diff -urb "$TEMP1" "$TEMP2"
rm -r "$TEMP1"
rm -r "$TEMP2"