On Fri, Aug 16, 2013 at 01:33:01PM +0200, Timothy Murphy wrote:

Some weeks ago, I asked if anyone had set up a backup scheme for a remote server. By backup here, I mean an alternative arrangement that can be called upon if eg the DSL connection to the remote machine fails.

I received one interesting reply:

At home, besides my fixed lines, I have two gsm-modems, one low-speed (that came free of charge with one of my fixed lines), the other is high speed, but pre-paid, normally off) ====================== I meant to respond at the time, asking for further details, but forgot, and now I have lost the original message.

I think that the original thread was on users@lists.fedoraproject.org:

http://www.spinics.net/linux/fedora/fedora-users/msg435811.html

In case the web/CLI interface of DSL modem/router is still responsive, you can script a reboot from the server on the LAN when fails the ping to a set of well-know always-up hosts.

I resuscitate this way a D-Link DSL-320B with (snippet):

# Set both international and national hosts. hosts="www.google.com www.yahoo.com www.libero.it www.telecom.it"

for h in $hosts; do ping -c 2 "$h" > /dev/null 2>&1 && { # Success retval=0 break }

echo "Ping failed for ${h}." retval=1 # Failure done

test "$retval" -ne 0 && { echo -e "\nResetting the ADSL modem." phantomjs adsl-reboot.js }

adsl-reboot.js is a Javascript script that logins onto the modem and "clicks" the reset button.

You can also play with the -w option if your ping supports it. The default timeout is 10 seconds or so.

Mihai

Timothy Murphy wrote:

The problem in both places is that the ADSL modem sometimes goes off, and the only way to turn it back on seems to be to disconnect and re-connect the power supply.

I had a similar problem with a cable modem. My relatively inexpensive solution was to buy an X-10 Firecracker kit and build bottlerocket from http://www.linuxha.com/bottlerocket/.

I then set up a cron job to test the Internet connection every minute and reset the power whenever it failed.

c

On 08/16/2013 01:33 PM, Timothy Murphy wrote:

Some weeks ago, I asked if anyone had set up a backup scheme for a remote server. By backup here, I mean an alternative arrangement that can be called upon if eg the DSL connection to the remote machine fails.

I received one interesting reply:

At home, besides my fixed lines, I have two gsm-modems, one low-speed (that came free of charge with one of my fixed lines), the other is high speed, but pre-paid, normally off) ====================== I meant to respond at the time, asking for further details, but forgot, and now I have lost the original message.

So now I am posting again, asking if anyone has implemented any such arrangement. If you have, I would be very interested to hear the details.

In my case, I spend time in two countries - Ireland and Italy - and have servers in each place. The problem in both places is that the ADSL modem sometimes goes off, and the only way to turn it back on seems to be to disconnect and re-connect the power supply.

I do not know how to find what I am looking for on net, so I will just try to explain how to reset your ADSL or other device via phone.

You can build a device that will use either power from phone/mobile speaker to charge capacitor that will in turn disconnect the power to any kind of device (power cord).

Idea is to dial that phones number and keep it ringing for a certain period of time. Impulses from the speaker (constant (polyphonic) melody) will keep charged a "electronic item/coil?" that will brake the power circuit/cable of your device. I usually kept it ringing for 10 seconds and after I stop calling, coil? will loose charge and return to the original position again closing the circuit and allowing to device to power up.

I am no engineer and my technical English is horrible, but I think any decent electrician/TV repairman should understand what I am talking about.

It's cheap and dirty manual trick, but when push comes to shove you can dial that phone and reboot the ADSL modem in no time.