> For the complete documentation index, see [llms.txt](https://xoops.gitbook.io/xoonips-tutorial/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://xoops.gitbook.io/xoonips-tutorial/3installation/4.-customize-centos5/45set_up_iptables.md).

# 4.5. Set up iptables

Set up for packet filtering.

At the initial condition, the access to the web server is controlled. The following shows how to set up for access permission.

| **\[root\@xoonips-server \~]# vi /etc/sysconfig/iptables**                         |                                          |
| ---------------------------------------------------------------------------------- | ---------------------------------------- |
| Copy the line below.                                                               |                                          |
| **-A RH-Firewall-l-INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT** |                                          |
| ↓ Change the "22" in the line to "80".                                             |                                          |
| **-A RH-Firewall-l-INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT** |                                          |
| **\[root\@xoonips-server \~]# /etc/init.d/iptables restart**                       | ← Restart the packet filtering software. |