Few questions regarding configuring Isilon at ESX

1. What if i have already given internal and external IP address for a node. How to change it later? When I login to a node, I am not sure what is the command to reconfigure the IP settings.

2. Is it possible if I create two separate nodes at two different time with different external and internal ip addresses. Can I add them into a single cluster later?

3. In doc, it ask me to give IP range for internal and external Ip addresses. What if the available IP addresses are not in sequence. How to give them discrete ip addresses (for example, *.*.*.56 and *.*.*.97)?

4. Can I give DHCP IPs for internal and external IP addresses? Can I make Isilon to choose the IP addresses by himself from the available vLAN?