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Hello!<br />
<br />
Just to warn you before reading this: I barely know enough about subnetting to get by so excuse any stupid questions please. Anyway, I am trying to set up two network segments separated by my PIX. When I try and change the inside IP of the PIX I get an error:<br />
<br />
pixfirewall(config)# show ip<br />
System IP Addresses:<br />
&nbsp; &nbsp; &nbsp; &nbsp; ip address outside 172.20.4.9 255.255.252.0<br />
&nbsp; &nbsp; &nbsp; &nbsp; ip address inside 192.168.1.1 255.255.255.0<br />
Current IP Addresses:<br />
&nbsp; &nbsp; &nbsp; &nbsp; ip address outside 172.20.4.9 255.255.252.0<br />
&nbsp; &nbsp; &nbsp; &nbsp; ip address inside 192.168.1.1 255.255.255.0<br />
pixfirewall(config)# ip address inside 172.20.6.1 255.255.252.0<br />
Sorry, not allowed to enter IP address on same network as interface 0<br />
<br />
With a subnet mask of 255.255.252.0 isn't 172.20.4.X on a different subnet as 172.20.6.X? Why is there a conflict?<br />
<br />
Thanks in advance.<br />
<br />
Mike
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Hello!

Just to warn you before reading this: I barely know enough about subnetting to get by so excuse any stupid questions please. Anyway, I am trying to set up two network segments separated by my PIX. When I try and change the inside IP of the PIX I get an error:

pixfirewall(config)# show ip
System IP Addresses:
        ip address outside 172.20.4.9 255.255.252.0
        ip address inside 192.168.1.1 255.255.255.0
Current IP Addresses:
        ip address outside 172.20.4.9 255.255.252.0
        ip address inside 192.168.1.1 255.255.255.0
pixfirewall(config)# ip address inside 172.20.6.1 255.255.252.0
Sorry, not allowed to enter IP address on same network as interface 0

With a subnet mask of 255.255.252.0 isn't 172.20.4.X on a different subnet as 172.20.6.X? Why is there a conflict?

Thanks in advance.

Mike

PIX 501: Inside/Outside IP Addressing

Software firewalls, also known as host-based firewalls, provide a layer of software on one host that controls network traffic in and out of that single machine. Most operating systems now include firewall software, but many available software firewalls include central distribution, antivirus systems and disaster recovery.

Software Firewalls

Cisco PIX is a dedicated hardware firewall appliance; the Cisco Adaptive Security Appliance (ASA) is a firewall and anti-malware security appliance that provides unified threat management and protection the PIX does not. Other Cisco devices and systems include routers, switches, storage networking, wireless and the software and hardware for PIX Firewall Manager (PFM), PIX Device Manager (PDM) and Adaptive Security Device Manager (ASDM).