> For the complete documentation index, see [llms.txt](https://johnpion.gitbook.io/admin-sky-blog/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://johnpion.gitbook.io/admin-sky-blog/citrixxenserver/gre.md).

# Using GRE tunnel

❗️ Can use it just when 2 servers commuticated direcly

## server1

**iptables**

```
-A INPUT -p gre -j ACCEPT
-A RH-Firewall-1-INPUT -i gre-temp -m conntrack --ctstate NEW -j ACCEPT
```

**kernel modules**

```shell
modprobe ip_gre
```

**ip link**

```shell
iptunnel add gre-temp mode gre local $SERVER1_IP remote $SERVER2_IP ttl 225
ip a add 10.10.10.1/30 dev gre-temp
ip link set gre-temp up
```

**temp web-server**

```shell
cd /mnt/$DIR
python -m SimpleHTTPServer
```

## server-2

**kernel modules**

```shell
modprobe ip_gre
```

**ip link**

```shell
iptunnel add gre-temp mode gre remote $SERVER1_IP local $SERVER2_IP ttl 225
ip a add 10.10.10.2/30 dev gre-temp
ip link set gre-temp up
```

Now you can use `wget` for quick transferring date via gre tunnel