Adjusting Linux Firewall Settings

In CentOS and other Linux distros, there may be firewall settings which prevent you from accessing ArangoDB. These can be configured through the “iptables” command.

Also see: https://wiki.centos.org/HowTos/Network/IPTables

To use iptables, you have to run as root (su).
Verify iptables is running
```
lsmod | grep ip_tables
```
CODE

List the current set of rules .

iptables -L

CODE

Here's a sample of output.

Chain INPUT (policy ACCEPT)
target     prot opt source               destination        
ACCEPT     all  --  anywhere             anywhere            state RELATED,ESTABLISHED
ACCEPT     icmp --  anywhere             anywhere           
ACCEPT     all  --  anywhere             anywhere           
ACCEPT     tcp  --  anywhere             anywhere            state NEW tcp dpt:ssh
REJECT     all  --  anywhere             anywhere            reject-with icmp-host-prohibited


Chain FORWARD (policy ACCEPT)
target     prot opt source               destination        
REJECT     all  --  anywhere             anywhere            reject-with icmp-host-prohibited

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

CODE

It might be necessary to add a rule to allow access to ArangoDB on port 8529.
Insert a rule in the INPUT chain, allowing Arango's default listening port (port 8529)
```
iptables -I INPUT 1 -p tcp --dport 8529 -j ACCEPT
```
CODE
Verify the rule was added.
```
iptables -L INPUT
```
CODE

Look for the following line:

ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:8529

CODE

Save the IPTABLES

CentOS

IPv4

iptables-save > /etc/sysconfig/iptables

CODE

IPv6

ip6tables-save > /etc/sysconfig/ip6tables

CODE

Debian or Ubuntu

IPv4

iptables-save > /etc/iptables/rules.v4

CODE

IPv6

ip6tables-save > /etc/iptables/rules.v6

CODE

Also see https://www.thomas-krenn.com/en/wiki/Saving_Iptables_Firewall_Rules_Permanently