Secured connection to network (Android + OpenVPN)

Maybe you are using free wifi hotspots in your favorite cafe, restaurant or on airport.

Maybe your GSM Carrier is tracking your traffic in internet, of course for profiling/ad cause (I’m looking at you T-Mobile, I remember that you inject your internet plans ads in Twitter app)

Security wise there is a lot more of danger waiting at you at those ‘free’ hotspots.

So what to do?

What if I told you that you can still can use those bad but free hotspot while having somekind of protection? That you could hide some of that sweet-sweet traffic for yourself…

The solution that I want to introduce to you is a VPN

 

You don’t have to root your android phone to use vpn.

“OpenVPN fo Android” will work with payed service as self-hosted one (this is how you can setup one)

 

Advanced settings that will save your battery:

To protect your connection VPN need to be connected all the time – vpn don’t know when your application will get push notification, or when your friend will make a wificall to you. So it can drain battery a bit more than without using it. But you don’t have to sacrifice your battery life that much. We can tweak some settings to make it less battery hungry.

Edit two options in your vpn server config file /etc/openvpn/server.conf:

Allow new TCP port to accept connection:

Now change one setting on your android openvpn client config:

Remember to restart/reload your openvpn server so the new config will be used.

 

small Warning: TCP Protocol wasn’t meant to be used with VPN connection, with unstable internet connection you can fell a bit discomfort, but still the battery drain will be significant lower than with UDP setting.

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Why I’m moving from Baikal to Radicale (CalDav & CardDav)

Saber/Dav which is a core component of Baikal is looking for maintainer (full story here)

It’s been some time now that I moved from Google Calendar service to self-hosted, open source solution.

I never notice any down sides with accessibility – maybe my need were simple enough 🙂

 

I’m not saying that Baikal is dead, if your are interested in Baikal fell free to lookup those posts (installation, updating)

 

As for me I started noticing one minor issue I had with Baikal, that is complicated calendar sharing setup – it IS possible to share calendars but its more complicated than it should be, it was announce that sharing will be added later after big code rewrite and I waited (because I wouldn’t even be able to contribute to php7.0+silex anyway), but here I found new solution… Radicale, it also don’t support sharing calendars via web-panel, but for me it got one BIG advanted in sharing zone, user rights, and with one little ACL list I was able to share whatever I wanted.

None of both solution support migration tools for this process so It was a bit of pain (as for now I wasn’t able to find too that would migrate my ‘Tasks’ from calendar, but I never used it as much and migration was done by hand with me clicking 2 buttons on each of 20 tasks I had left)

 

If you are interested, here are links related to process of installing, configure and migrate data from one solution to other:

  • Links coming soon

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Bootloop into recovery after flashing custom firmware

Sometimes you get loop into recovery after flashing custom rom, there is a simple solution to this:

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Dovecot – Proper IDLE timeout for android phones

If you are using your own imap server with android you could (but not nesesery) notice bigger battery drain and email application being on top of application that drain battery.

This could be a server side problem, because default dovecot configuration have idle_timeout set to 2minuts, so basicly every 2 minuts your phone query/poll imap server information about new emails – which results in higher battery drain.

Lets evalueate this with simple shell command:

This should result i:

The interval between each ‘OK still here’ is that your imap clean see/does. By default this should be 2minut interval.

Let us change this:

systemctl restart dovecot.service

And we are done.Facebooktwittergoogle_plusreddit

Google Authenticator – manual backup and restore

If we have ROOT access we can manualy backup the file that contains seeds needed to generate password in application.

Backup: You need to set ROOT access for ADB, and then:

The content of the file can be display with help of sqlite client application:

The above method can be done with file manager that can get ROOT access

Restore backup: You need to set ROOT access for ADB, and then:

The above method can be done with file manager that can get ROOT access and copy databases file to:

Also remember to set ownership for proper application user (com.google.android.apps.authenticator2) on this file, because with wrong one (root) the application will crash every time you try to open it.

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