Dear All,
Thank you VERY much creators and developers of eblocker.
I'm new to this forum, and eblocker, and unfortunately absolutely no expert on embedded linux and this type of devices. I discovered eblocker reading an article in a local computer magazine, and thought it to be perfect for me. Ad filtering, openvpn server and client, in one, easily configurable. Plus the ability to do per device setup, and coming in through the openvpn server, and going out again via the client to tor or a openvpn compatible provider. To date I used a vpn client gateway in combination with pi-hole on a raspberry pi. A setup created by a person called mr-canoehead.
With eblocker I'm currently using as test a raspberry pi 3b+ to see if it's worth the purchase of a raspberry pi 4b.
Encountering some strange problem though for which I do not have an explanation, and am hoping someone else can shed some light on eblckers behavior.
-Raspberry pi 3b+
-eblocker 2.5.8, ALL standard, no changes to default filterlists + nightly updates
-Expert network mode
-Fixed IP address, mask, DNS (cloudfare and main google as 3rd choice 1.1.1.1 + 1.0.0.1 + 8.8.8.8) and gateway
-Only 1 computer is activated for eblocker, others are disabled.
-That 1 computer uses the eblocker IP address as DNS, but not as gateway.
-No https active
-Firefox 49 (due to security camera requirements) on windows 10
-No VPN, no Tor enabled
I do not think anything of the above is of influence on this problem, but your readme required me to add it.
I have many devices on my network, for which only 1 is activated for eblocker, being above described computer config. There's 1 DDWRT router functioning as VPN gateway, not activated for eblocker. Another DDWRT router functions as wifi AP, also not activated for eblocker. A synology nas which uses the DDWRT VPN gateway for DNS and as gateway.
Internet connection, and land phoneline, through a cable provider. It's modem is not activated for eblocker, nor can it be according the eblocker devices list. No enable switch in front of it. It is the internet gateway.
Problem:
When eblocker is activated the data LED for the land phoneline on my providers modem, and the data LED on the DDWRT VPN gateway are continuesly blinking. None of these devices are activated for eblocker. After shutdown of eblocker, this stops immediately.
Question:
What is eblocker doing accessing my providers phone data connection, and accessing my DDWRT VPN gateway?
Hope someone can shed some light on this behavior, because for now I do not understand this, and thus do not know if I can trust this.
Thanks and best regards,
@droopy Long question for a simple answer: eBlocker uses ARP spoofing to catch the packets before they hit your router. This results in IP packets being sent constantly to all devices - which is shown by the LED.
See here how to disable: https://eblocker.org/community/bugs-features/howto-disable-arp-spoofing/
As you mentioned you are using a Raspi 3: There is a known bug in the Linux that freezes Raspi 3. So you might want to upgrade to Raspi 4.
THX!
THANK YOU very much for this quick insight. And indeed, a long question, but since it's my 1st time with eblocker and its forum I thought it be best to include all regarding devices and situation.
The by you referred bug I've already experienced, and found that searching the forum. For the moment it was only for testing, and I had this raspberry pi 3b+ lying around, so the choice was easy.
So ARP spoofing, that scared me a bit, at least what I already knew about it, and now also reading the information for it on the internet. I now also found some info for it on the forum, so I'm gonna have a good read into that as well.
Thanks again for the quick heads-up.
ARP spoofing, that scared me a bit
No need to worry. We use this „hacker technique“ to easily plug & play eBlocker for users without network knowledge. If you are a tech geek or know IP networking basics you can disable ARP spoofing as discussed under the link above.
THX!
Just as information for others.
My problem was not the ARP spoofing, as I already had the eblocker in expert mode. My problem was the device discovery as pointed towards by Boris Prinz in the linked thread from Random.
My devices are now not anymore trying to mimic the Las Vegas strip 😉
I'm continuing my testing, but I think this is definitely worth the purchase of a Raspberry Pi 4. I wish I'd found this eblocker long ago. Would have saved me a lot of headaches trying to figure out setups using guides on the internet and SSH terminals. Aaah, at least I learned from it.
Happy seasonal holidays to all and a Covid19 free days. Stay safe.