OS X: How to avoid having to re-connect to network share after NAS was turned off?

Solution 1:

You will be able to get re-connect working with Autofs.

Apple has published a technical white paper on Autofs
http://images.apple.com/business/docs/Autofs.pdf

There is a comprehensive blog article by Rajeev Karamchedu
http://rajeev.name/2007/11/22/autofs-goodness-in-apples-leopard-105-part-i/

Also there is a third party application named AutomountMaker that enables this using GUI
http://jm.marino.free.fr/index.php?switch=sw_&title=AutomountMaker
(personally haven't used this software though)

Here is my setup using indirect mapping

(I personally use smb but afp should just work)

1. edit master map file to add your custom map

   # sudo vi /etc/auto_master

   +add line
   

   /Network/NAS nas_map

2. create /etc/nas_map add a following line

   # sudo vi /etc/nas_map

   +add line (note that you can add more than one line here)
   

   SHARE_NAME  -fstype=afp afp://USER:PASS@NAS_NAME/SHARE_NAME

   SHARE_NAME - directory name you want use to map /Network/NAS/SHARE_NAME
   USER:PASS - username and password (use 'guest' for anonymous login)
   NAS_NAME - name of your nas or the ip address
   SHARE_NAME - name of your share set by your NAS
   

   alternatively you can use following line to use smb instead of afp
   SHARE_NAME -fstype=smbfs ://USER:PASS@NAS_NAME/SHARE_NAME

3. Set the permission on your map file

   # sudo chmod 600 /etc/nas_map

4. Reload automount

   # sudo automount -vc

You now have access to your NAS via /Network/NAS/SHARE_NAME directory. When your server goes offline, you should be able to auto-connect to your NAS when it comes back online.