We have a hodgepodge of systems that are either static IP addresses, or DHCP reservations. (We don't hand out any addresses except reserved ones). Some servers have multiple Nics, and ILO cards. Its getting annoying to have to scan the subnet to find free IP's to be able to use, especially because a server might be offline for a few mintues when I perform the scan. Any listing seems to be forgotten about quickly..
I would like to create a reservation for every single IP address in my subnets. That would make things quite a bit easier to manage/view. (and afterwards, look at setting up DHCP to do DNS updates too)
I have run the following command:
sudo arp-scan -I eth0 10.10.10.0/24
And have a list of all IP's and Mac Addresses. I am about to get a list of all host/dns names as well. (and if they don't have a hostname, I will call it ip-last octet, so for 10.10.10.100, "ip-100".). That is easy to do with some work in Open Office Calcl
Is there a way to automagically add reservations to the dhcpd.conf file?
I really don't want to hand edit this, as there are hundreds (multiple subnets).
is there an easy way I can call a command to create a reservation, or import a list from CSV? I could find many ways to do this with Windows DHCP, using Net Sh, but not with my CentOS based DHCP server.
I would rather use an existing way, then have to write my own tool.
TL:DR - I need a way to modify Cento's DHCPd from the command line, like you can in Windows with Netsh