improve 7.3 upgrade process & redius setup

Fixes
https://github.com/gitlabhq/gitlabhq/commit/2b35c887904b6a7a05a7c88fdf1ccd66ba943e20#commitcomment-7829537,
https://github.com/gitlabhq/gitlabhq/commit/5704e6fee9d2dea67c4a91b43d06a9958484d29b#commitcomment-7829367,
&
https://github.com/gitlabhq/gitlabhq/commit/5704e6fee9d2dea67c4a91b43d06a9958484d29b#commitcomment-7829381

doc/install/installation.md

@@ -139,7 +139,12 @@ We recommend using a PostgreSQL database. For MySQL check [MySQL setup guide](da
 
     # Configure redis to use sockets
     sudo cp /etc/redis/redis.conf /etc/redis/redis.conf.orig
-    sed -e 's/^# unixsocket /unixsocket /' -e 's/^port .*/port 0/' /etc/redis/redis.conf.orig | sudo tee /etc/redis/redis.conf
+    
+    # Disable Redis listening on TCP by setting 'port' to 0
+    sed 's/^port .*/port 0/' /etc/redis/redis.conf.orig | sudo tee /etc/redis/redis.conf
+
+    # Enable Redis socket for default Debian / Ubuntu path
+    echo 'unixsocket /var/run/redis/redis.sock' | sudo tee -a /etc/redis/redis.conf
 
     # Activate the changes to redis.conf
     sudo service redis-server restart
@@ -210,7 +215,7 @@ We recommend using a PostgreSQL database. For MySQL check [MySQL setup guide](da
     # Configure Redis connection settings
     sudo -u git -H cp config/resque.yml.example config/resque.yml
 
-    # Change the Redis socket path if necessary
+    # Change the Redis socket path if you are not using the default Debian / Ubuntu configuration
     sudo -u git -H editor config/resque.yml
 
 **Important Note:** Make sure to edit both `gitlab.yml` and `unicorn.rb` to match your setup.

doc/update/6.0-to-7.3.md

@@ -80,7 +80,6 @@ For GitLab Enterprise Edition:
 sudo -u git -H git checkout 7-3-stable-ee
 ```
 
-
 ## 4. Install additional packages
 
 ```bash
@@ -95,21 +94,22 @@ sudo apt-get install pkg-config cmake
 
     # Configure redis to use sockets
     sudo cp /etc/redis/redis.conf /etc/redis/redis.conf.orig
-    sed -e 's/^# unixsocket /unixsocket /' -e 's/^port .*/port 0/' /etc/redis/redis.conf.orig | sudo tee /etc/redis/redis.conf
+    # Disable Redis listening on TCP by setting 'port' to 0
+    sed 's/^port .*/port 0/' /etc/redis/redis.conf.orig | sudo tee /etc/redis/redis.conf
+    # Enable Redis socket for default Debian / Ubuntu path
+    echo 'unixsocket /var/run/redis/redis.sock' | sudo tee -a /etc/redis/redis.conf
     # Activate the changes to redis.conf
     sudo service redis-server restart
     # Add git to the redis group
     sudo usermod -aG redis git
 
-    cd /home/git/gitlab
     # Configure Redis connection settings
     sudo -u git -H cp config/resque.yml.example config/resque.yml
-    # Change the Redis socket path if necessary
+    # Change the Redis socket path if you are not using the default Debian / Ubuntu configuration
     sudo -u git -H editor config/resque.yml
 
-    cd /home/git/gitlab-shell
     # Configure gitlab-shell to use Redis sockets
-    sudo -u git -H sed -i 's|^  # socket.*|  socket: /var/run/redis/redis.sock|' config.yml
+    sudo -u git -H sed -i 's|^  # socket.*|  socket: /var/run/redis/redis.sock|' /home/git/gitlab-shell/config.yml
 
 ## 6. Update gitlab-shell
 

doc/update/7.2-to-7.3.md

@@ -70,21 +70,22 @@ sudo cp lib/support/init.d/gitlab /etc/init.d/gitlab
 
     # Configure redis to use sockets
     sudo cp /etc/redis/redis.conf /etc/redis/redis.conf.orig
-    sed -e 's/^# unixsocket /unixsocket /' -e 's/^port .*/port 0/' /etc/redis/redis.conf.orig | sudo tee /etc/redis/redis.conf
+    # Disable Redis listening on TCP by setting 'port' to 0
+    sed 's/^port .*/port 0/' /etc/redis/redis.conf.orig | sudo tee /etc/redis/redis.conf
+    # Enable Redis socket for default Debian / Ubuntu path
+    echo 'unixsocket /var/run/redis/redis.sock' | sudo tee -a /etc/redis/redis.conf
     # Activate the changes to redis.conf
     sudo service redis-server restart
     # Add git to the redis group
     sudo usermod -aG redis git
 
-    cd /home/git/gitlab
     # Configure Redis connection settings
     sudo -u git -H cp config/resque.yml.example config/resque.yml
-    # Change the Redis socket path if necessary
+    # Change the Redis socket path if you are not using the default Debian / Ubuntu configuration
     sudo -u git -H editor config/resque.yml
 
-    cd /home/git/gitlab-shell
     # Configure gitlab-shell to use Redis sockets
-    sudo -u git -H sed -i 's|^  # socket.*|  socket: /var/run/redis/redis.sock|' config.yml
+    sudo -u git -H sed -i 's|^  # socket.*|  socket: /var/run/redis/redis.sock|' /home/git/gitlab-shell/config.yml
 
 ### 6. Update config files
 
@@ -96,6 +97,11 @@ There are new configuration options available for gitlab.yml. View them with the
 git diff 7-2-stable:config/gitlab.yml.example 7-3-stable:config/gitlab.yml.example
 ```
 
+```
+# Use the default Unicorn socket backlog value of 1024
+sudo -u git -H sed -i 's|^:backlog => 64|:backlog => 1024|' config/unicorn.rb
+```
+
 * HTTP setups: Make `/etc/nginx/sites-available/nginx` the same as https://gitlab.com/gitlab-org/gitlab-ce/blob/7-3-stable/lib/support/nginx/gitlab but with your settings.
 * HTTPS setups: Make `/etc/nginx/sites-available/nginx-ssl` the same as https://gitlab.com/gitlab-org/gitlab-ce/blob/7-3-stable/lib/support/nginx/gitlab-ssl but with your setting