Modify your Firewall for a Static Internal IP Address

Modify your Firewall for a Static Internal IP Address
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This procedure describes converting your firewall to operate in an environment with static IP addressing internally (on the protected side). It is also useful in the event that you do not use the default 192.168.1.0 network address. This procedure assumes that you have gone through the Initial Configuration already. Items that look like: <???_from_block_n> refer to block n from the Network Information Sheet.

Log into the firewall as root.
If you will be using the default internal IP address of 192.168.1.254, press [q] then [Enter] to exit to the shell, and go on to step 20.
At the configuration menu, select [1] for Network Settings.
At the Network Configuration menu, select [1] for Network Configuration.
In the Interfaces section, scroll down to the eth1_* variables.
Locate the line that reads eth1_IPADDR=192.168.1.254.
Change this line to read:
```
eth1_IPADDR=<ip_from_block_9>
```
Locate the line that reads eth1_MASKLEN=24
Change this line to read:
```
eth1_MASKLEN=<masklen_from_block_15>
```
Locate the line that reads eth1_BROADCAST=+.
Change this line to read:
```
eth1_BROADCAST=<bcast_from_block_10>
```
Scroll down to the Internal interface section.
Locate the line that reads INTERN_NET=192.168.1.0/24.

Change this line to read:

eth1_BROADCAST=<netnum_from_block_14>/<masklen_from_block_15>

Locate the line that reads INTERN_IP=192.168.1.254.
Change this line to read:
```
eth1_BROADCAST=<ip_from_block_9>
```
Press [Ctrl]-[s] to save this file.
Press [Ctrl]-[q] to return to the menu.
Press [q] then [Enter], then [q] then [Enter] again to return to the shell.
Mount the floppy disk into the file system:
```
mount -t msdos /dev/fd0u1680 /mnt [Enter]
```
for Dachstein floppy-only distributions -or-
```
mount -t msdos /dev/fd0 /mnt [Enter]
```
for Dachstein CD or dual-floppy firewalls
Change to the floppy drive:
```
cd /mnt [Enter]
```
Edit the syslinux.cfg file:
```
e3 syslinux.cfg [Enter]
```
Locate the line that begins default linux.
In this line, locate the section that begins LRP=.
In this section, delete the dhcpd entry, and the comma following it.
Press [Ctrl]-[s] to save this file.
Press [Ctrl]-[q] to return to the shell.
Edit the lrpkg.cfg file:
```
e3 lrpkg.cfg [Enter]
```
Delete the dhcpd entry, and the comma following it.
Press [Ctrl]-[s] to save this file.
Press [Ctrl]-[q] to return to the shell.
Remove the dhcpd.lrp package fro the disk:
```
rm dhcpd.lrp [Enter]
```
Note
This step applies to Floppy only distributions, and is optional. If you do not plan on adding additional packages to your firewall (thus no additional free space on the floppy is required) you can leave this file here. You may also want to copy this file to another floppy to maintain a copy in case you decide to add the dhcp server back in at a later time.
Move to the root directory:
```
cd / [Enter]
```
Unmount the floppy disk:
```
umount /mnt [Enter]
```
Load the lrcfg script:
```
lrcfg [Enter]
```
Now back up the firewall. If your firewall was unmodified prior to performing this procedure, you need only back up the etc package. If you retained the default settings for the IP address (that is, you skipped steps 3 - 19) you do not need to back up the firewall.

Modify your Firewall for a Static Internal IP Address

Note