A. Changes to shipside SCN

1. Edit /etc/hosts to change relevant hostname/IP address pairs.
   
   
2. Using given SCN IP and network IP, determine netmask and broadcast IPs.
   
   Guidelines can be found at http://www.ibiblio.org/pub/Linux/docs/HOWTO/mini/IP-Subnetworking or perhaps http://netfilter.kernelnotes.org/unreliable-guides/networking-concepts-HOWTO-4.html#ss4.1
   
   
3. Edit /etc/sysconfig/network-scripts/ifcfg-eth0:0
   
   Replace definitions for IPADDR, NETWORK, NETMASK, BROADCAST
   
   
4. Edit /etc/sysconfig/static-routes
   
   Replace old IP address(es) with new.
   
   
5. Reconfigure SCN router routing table.
   
   a. Connect to router via 'telnet 172.16.xx.2' or 'minicom router_ttyS1'
   
   b. Once connected/logged on
   
   scn-rou> ena
   passwd: xxxxxxx
   scn-rou# show running-config
   

• Find 'ip route' statement that contains the old network IP. Record.
  
  scn-rou# config terminal
  
  
• Remove old route. Place 'no' in front of 'ip route' found above.
  
  scn-rou# no ip route xxx.xxx.xxx.xxx 255.255.255.xxx 172.16.xx.1
  
  
• Add new route. Replace old IP with new in 'ip route' statement.
  
  scn-rou# ip route yyy.yyy.yyy.yyy 255.255.255.yyy 172.16.xx.1
  scn-rou# exit * from 'config terminal'
  scn-rou# save running-config startup-config
  scn-rou# show startup-config * confirm changes
  
  
• exit

B. Changes to shoreside NICs

1. Edit NIC /etc/rc.d/rc.local
   
   It's necessary to know the network IP and the short form of the netmask, i.e.,
   
   

   Short Form	Full Form	Maximum # of Machines
   /24	/255.255.255.0	255
   /25	/255.255.255.128	127
   /26	/255.255.255.192	63
   /27	/255.255.255.224	31
   /28	/255.255.255.240	15
   /29	/255.255.255.248	7
   /30	/255.255.255.252	3

   
   
   a. Remove masquerade entries for old IP (or comment with '#')
   b. Add masquerade entries for new IP
2. Place new rule into running kernel
   
   Copy new entry from rc.local and run as root in shell window.
   
   
3. Remove old ipchains entry from kernel
   
   nic # ipchains --line --list fwd
   results in a listing of rules denoted by a number in left column.
   Note number of rule to remove. Confirm new rule(s) are in place.
   
   nic # ipchains -D fwd number
   
   nic # ipchains --line --list fwd
   
   
4. Edit NIC router config
   
   a. Connect to router via 'minicom router_ttyS1'
   
   b. Once connected/logged on
   
   scn-rou> ena
   passwd: xxxxxxx
   scn-rou# show running-config

• * Find 'ip route' statement that contains the old network IP. Record.
  
  scn-rou# config terminal
  
  
• Remove old route. Place 'no' in front of 'ip route' found above.
  
  scn-rou# no ip route xxx.xxx.xxx.xxx 255.255.255.xxx 172.16.xx.2
  
  
• Add new route. Replace old IP with new in 'ip route' starement.
  
  scn-rou# ip route yyy.yyy.yyy.yyy 255.255.255.xxx 172.16.xx.2
  scn-rou# exit * from 'config terminal'
  scn-rou# save running-config startup-config
  scn-rou# show startup-config * confirm changes
  
  
• exit