Weird DPI (Deep packet inspection) related problem

[partymonger]

I am literally about to pull my the hair out of my head. Thats how mad I am right now cause I cant make any sense of this.

I use Green Tunnel on my laptop (mac) to bypass bsnl Deep packet inspection. How do I know BSNL has DPI? I use green tunnel and sites like t0rrents work.
So I am able to access them on laptop with GT, but not on phones etc.


Now here's where it gets weird. I am developing my own site. (Literally just in the starting phase but domain is old.)

I was using it on my workstation till 3am - works fine.
Earlier in the day, on my laptop- Works fine.

at 3am on my laptop - NOT WORKING. Chrome says -"
This site can’t be reached
sitename.com refused to connect"

So I spend hours wondering if the new VPS is the issue? The new stack im building on? or something else out of the thousand things in between. Literally at my wits end by 5am. I realize, lets check it on the phone - bam working!

Then i realize Green tunnel is off on the laptop. Lets switch it on. SUDDENLY IT WORKS.

In short-
Since evening the website wont open on laptop without GREEN Tunnel. Opens everywhere else. And I have. a headache now.

My point of concern is - Is the BSNL inspection a bit too smart or stupid or just plain fucked now?

My DNS varies from 1.1.1.1, 8.8.8.8 to my custom pi hole on diff devices.

 

[partymonger]

On the plus side, If there is anyway to confirm DPI exists and its blocking my site (Only on the laptop? lol) Then I have complete access to server and i can F**k bsnl up if you guys can reccomend some tests.

Another thing - A second site on the same server works fine. Which is why I kept thinking the server was the issue.

 

[partymonger]

More Interesting stuff-

At around 5.30am my internet gets disconnected and unable to reconnect. I restart the modem and router. Suddenly I cant get into the router!?! The password of the router has been changed on its own. I use the default optilink one and change back to my old.

Now it gets more interesting. There is no EPON signal now!

Laser Device Info

Tx Power	2.325908 dBm
Rx Power	-inf dBm
Temperature	44.589844 C
Voltage	3.362800 V
Bias Current	23.400000 mA

What the hell is going on here :O
No internet as of now.

 

[vignesh_venkatesan]

DPI is used for traffic shaping and site blocking by most isps.
This is usually the error message you get if your site is blocked by dpi.

 

[abbyck]

In short-
Since evening the website wont open on laptop without GREEN Tunnel. Opens everywhere else. And I have. a headache now.

GreenTunnel has some problems while exiting. This does not happen always.
GT misses doing the cleanup steps while exiting. After exiting GT and if the system proxy is unset, the system will try to connect through the proxy (Which is not running anymore).
I don't know how do they set a system-wide proxy in Mac OS.
In Gnome you can check the proxy set greping on environment variables

$ env | grep proxy

.
While running GT http_proxy env var will be set to http://127.0.0.1:8000/

http_proxy=http://127.0.0.1:8000/

When GT misses to do the clean up you can just unset http_proxy.

unset http_proxy

and GT proxy will be removed.


BTW this is has nothing to do with BSNL. I have seen this problem even with windows.

No signal might be due to some cable cuts or ONU problem. Still nothing related with DPI or GT.

Maybe for MacOS, you can do the things mentioned in here manually.

 

[varkey]

Good point @abbyck That sounds definitely plausible. DPI definitely didn't explain the issue, and I don't think BSNL does any DPI.

 

[partymonger]

I checked with the LCO/TIP and he said BSNL exchange inverters failed in the morning leading to network being down for 6-7 hrs (last checked at 12.30pm.) But I am still unable to connect via PPPOE. Request to connect still times out. ("pppd[1329]: Timeout waiting for PADO packets")

That still does not explain why my modem reset automatically.

 

[varkey]

Perhaps the OLT rebooted and it tried to re-provision all connected ONTs? If you are using a supported ONT, the OLT could remotely reconfigure or provision it, I suppose.

 

[partymonger]

GreenTunnel has some problems while exiting. This does not happen always.
GT misses doing the cleanup steps while exiting. After exiting GT and if the system proxy is unset, the system will try to connect through the proxy (Which is not running anymore).
I don't know how do they set a system-wide proxy in Mac OS.
In Gnome you can check the proxy set greping on environment variables

$ env | grep proxy

.
While running GT http_proxy env var will be set to http://127.0.0.1:8000/

http_proxy=http://127.0.0.1:8000/

When GT misses to do the clean up you can just unset http_proxy.

unset http_proxy

and GT proxy will be removed.


BTW this is has nothing to do with BSNL. I have seen this problem even with windows.

No signal might be due to some cable cuts or ONU problem. Still nothing related with DPI or GT.

Maybe for MacOS, you can do the things mentioned in here manually.

Thanks for the reply mate, thats a good insight into how GT works. Here's a few details -

1) I never exit Green Tunnel ever. Starts with system and closes with system. Its either on or off (green or red). Never exit it. It could be that MAC OS maybe puts it in some pwoer saving mode, but i've never seen that. It does slow down sometimes ("Chrome status below says something along the line of "waiting for http tunnel")

2) These 2 sites I mention are on the same IP address. The only thing different is the domain name ! And that could be the only thing beign filtered.

3) The other devices are on the same network. So if its DPI why isnt that intercepted? Is there something special with MAC OS? or Green Tunnel? GT on or Off, how do all other sites work? How does same laptop open the site when connected via hotspot the next second and not when connected via bsnl? Could this be some server side ban by failtoban or the server firewall? might have to check.

4) It really makes you want to check the 99999 other things in between. To be fair I have checked server logs, nginx logs, php logs and what not. I have been using the same stack for the server since 2013. Never seen anything like this. It drove me crazy last night when I just wanted to see how site is looking on laptop.

 

[partymonger]

BSNL is doing DPI that's for sure. Leetx and other sites dont open otherwise. It might be only in some parts. but it sure is there.