GRE tunneling help - Printable Version

GRE tunneling help - Printable Version

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GRE tunneling help - Bradlant™ - Apr 15, 2013

Hello,
Recently, I've had a troll come on my Minecraft server, and DDoS us for a good 30-120 minutes at a time for NO reason at all. I bought a DDoS protected VPS, to tunnel through, but every time I try, it says

# iptunnel add gre1 mode gre local **.***.***.** remote **.***.***.** ttl 255

ioctl: No such device

And I found a solution to that. Load a module. When I try to load it, it says this :

# modprobe ip_gre
FATAL: Could not load /lib/modules/3.2.13-xxxx-std-ipv6-64/modules.dep: No such file or directory

I've looked up that issue, so much. I think I've wasted about 2-3 hours looking for the answer on how to fix that.
I saw you could do a "Kernal Reload" (I think that's what it's called.) But my worries are that it will delete all my servers data.

I'm farely new to Linux.

The Operating system my server is currently running on is Ubuntu, and the server host is OVH

Thanks to all of you who help me!

* - Fa-koff - Apr 16, 2013

I'm not sure of how you're trying to 'tunnel' nor why, but most times you can simply use ssh to dynamically forward traffic through your sshd on your server.
The following sets up a SOCKS5 proxy on localhost using port 8080:

Code

ssh -C -D 8080 -fN [email protected]

The "-C" means compress the data; the "-D" means "Dynamic Forwarding; "8080" = local port; the "-fN" means to fork the process to the background, and Not to execute commands on the remote host.

Then setup your application to use the ssh connection, which depends on which app you're trying to use.

Example for Chrome/Chromium:

Code 
chrome --proxy-server="socks://localhost:8080"

For Firefox go to Preferences > Advanced > Network > Settings;
Choose "Manual Proxy..." type "localhost" in the "SOCKS Host" field and check "SOCKS v5" and set the port to the same one you used in the first command - in this case it's "8080."
Spoiler (Click to View)
Then go to a new tab (Ctrl + T) and type:

Code 
about:config

in the URL field.
Click through the nag screen, and type the following into the "Search" field:

Code 
remote

This should return something about "blah-blah-remote.dns..." where you right-click on the last field to "Toggle" from "False" to "True." (this sends your DNS requests through the SSH connection)
Spoiler (Click to View)
Close out of that, and open some site that tells you what your IP address is to see if you're using the SSH "tunnel."

Spoiler (Click to View)

* - Bradlant™ - Apr 16, 2013

(Apr 16, 2013 06:48 PM)Fa-koff Wrote: I'm not sure of how you're trying to 'tunnel' nor why, but most times you can simply use ssh to dynamically forward traffic through your sshd on your server.
The following sets up a SOCKS5 proxy on localhost using port 8080:

Code
ssh -C -D 8080 -fN [email protected]
The "-C" means compress the data; the "-D" means "Dynamic Forwarding; "8080" = local port; the "-fN" means to fork the process to the background, and Not to execute commands on the remote host.

Then setup your application to use the ssh connection, which depends on which app you're trying to use.

Example for Chrome/Chromium:

Code
chrome --proxy-server="socks://localhost:8080"

For Firefox go to Preferences > Advanced > Network > Settings;
Choose "Manual Proxy..." type "localhost" in the "SOCKS Host" field and check "SOCKS v5" and set the port to the same one you used in the first command - in this case it's "8080."
Spoiler (Click to View)
Then go to a new tab (Ctrl + T) and type:

Code
about:config
in the URL field.
Click through the nag screen, and type the following into the "Search" field:

Code
remote
This should return something about "blah-blah-remote.dns..." where you right-click on the last field to "Toggle" from "False" to "True." (this sends your DNS requests through the SSH connection)
Spoiler (Click to View)
Close out of that, and open some site that tells you what your IP address is to see if you're using the SSH "tunnel."

Spoiler (Click to View)

I've been getting MASSIVE long DDoS attacks. My provider doesn't provide DDoS protection, and I can't offord real protection. I've got a VPS with a 1 gig uplink, plus 4GBPS protection, I want to make my players connect to that VPS, then have the VPS send the data to my real un-protected server.

* - Fa-koff - Apr 16, 2013

Setup your sshd_config to only allow connections from specified users from their respective IP addresses using public keys, deny all extraneous connections.

Then setup your firewall to drop all connections except those you want to allow.

* - Bradlant™ - Apr 16, 2013

(Apr 16, 2013 07:13 PM)Fa-koff Wrote: Setup your sshd_config to only allow connections from specified users from their respective IP addresses using public keys, deny all extraneous connections.

Then setup your firewall to drop all connections except those you want to allow.

I host a Minecraft server. That'd not really work out... Population-wize

* - Fa-koff - Apr 16, 2013

Why not?
You should already have the necessary information, you've got the computer... Use it.

* - Bradlant™ - Apr 16, 2013

(Apr 16, 2013 07:15 PM)Fa-koff Wrote: Why not?
You should already have the necessary information, you've got the computer... Use it.

By what you said, it made it sound like I'd have to add each individual player IP.
Thanks for the help, by the way!

* - Fa-koff - Apr 16, 2013

Yes, you'll need to add the allowed IP addresses, and you already have that information in /var/log/auth.log

Just cat | grep through the file for the username/IP address combos and > to a text file from where you can use this list to populate your sshd_config and your firewall rule set.

I suggest that you do some more reading regarding all of the steps involved in order to gain understanding.

* - UnspokenOne - Apr 17, 2013

In regards to your GRE problem, your kernel probably doesn't have support for loadable modules (and/or you don't have the GRE module)... you would need to rebuild your kernel.

* - Bradlant™ - Apr 17, 2013

(Apr 17, 2013 10:09 AM)UnspokenOne Wrote: In regards to your GRE problem, your kernel probably doesn't have support for loadable modules (and/or you don't have the GRE module)... you would need to rebuild your kernel.

I figured. My host (OVH) wouldn't assist me, at all. I ended up just giving up on them, and switching to SecuredServers.

Thanks for the replies!