View source for Working DNS During Downtime

Here's how you can use a regular DNS server other than your HDA, and still access your HDA's dashboard, applications, etc. using their hostnames.

''This would allow you to browse the internet without problems, if your HDA is ever offline.''

Note that this will only work with '''Linux and Mac OS X''' clients, unless you find a way to re-create the crontab entry into it's Windows equivalent (installing Cygwin would be a good first step).

Once you have this working, you could even re-enable your router DHCP, and if you have static IPs configured on your HDA, make sure to re-create those entries in your router config.

==Prerequisites==

# You need to have setup [[Key-Based SSH Logins]] on each of your client computer you want to use this on. This is needed becase a cron entry will trigger a script every minute, and this script needs to be able to login on the HDA as you, and execute a script.<br/><br/>
# You need sudo access on your client computer(s), with the NOPASSWD option. This is needed to be able to overwrite the local /etc/hosts file. I'll let you figure out how to do that (Google?)

==On your HDA==
===Logged in as your regular user===
Note: Replace '''your_username''' with your Fedora username (for example ''joe'').

<div style="border: 1px solid #A3B1BF; padding: .5em 1em; color: #000; background-color: #E6F2FF; margin: 3px 3px 1em 3px;">
cd /home/'''your_username'''<br/>
mkdir bin<br/>
cd bin<br/>
wget http://wiki.amahi.org/images/3/32/Hda-get-hosts.sh<br/>
mv Hda-get-hosts.sh hda-get-hosts<br/>
chmod +x hda-get-hosts
</div>

===Logged in as root===
Notes:
*Use '''su -''' to become root in an already opened terminal window.<br/>
*Replace '''your_username''' with your Fedora username (for example ''joe'').

<div style="border: 1px solid #A3B1BF; padding: .5em 1em; color: #000; background-color: #E6F2FF; margin: 3px 3px 1em 3px;">
echo "'''your_username''' ALL = NOPASSWD: /home/'''your_username'''/bin/hda-get-hosts" >> /etc/sudoers
</div>

==On your client(s)==

Add the following entry in your crontab ('''crontab -e''' to edit your crontab).<br/>
Note: Replace '''your_username''' with your Fedora username (for example ''joe'').

<div style="border: 1px solid #A3B1BF; padding: .5em 1em; color: #000; background-color: #E6F2FF; margin: 3px 3px 1em 3px;">
<nowiki>* * * * *</nowiki> ssh '''your_username'''@hda "sudo bin/hda-get-hosts" > /tmp/hosts.hda ; grep -v "From HDA$\|Amahi HDA$" /etc/hosts > /tmp/hosts.new ; echo "# The following lines were added from your Amahi HDA" >> /tmp/hosts.new ; cat /tmp/hosts.hda >> /tmp/hosts.new ; sudo cp -f /tmp/hosts.new /etc/hosts
</div>

==Test==

Both commands should return your HDA internal IP address:

<div style="border: 1px solid #A3B1BF; padding: .5em 1em; color: #000; background-color: #E6F2FF; margin: 3px 3px 1em 3px;">
ping -c 1 hda | grep from<br/>
ping -c 1 hda.home.com | grep from
</div>

==DNS configuration on client(s)==

You have two choice:
#You [[Turning off DHCP|disable the DHCP]] on your HDA, and replace it with your router's DHCP. Don't forget to re-configure static IPs you had configured on your HDA into your router, and to [[RenewIP|renew the IP address]] on the client(s).
#You manually configure the DNS servers on your client computers to use your router as their DNS server (or any other DNS that is not your HDA). You HDA will continue to act as DHCP server, and will ask clients to use it as their DNS server, but as long as you can manually override that, you'll be fine.