Messing around with DHCP for the raspberry pi that’s going to be aggregating syslogs.
- Raspberry Pi running 32 bit Centos 7; primary interface addressed using DHCP.
- I assigned it a static DHCP allocation, a different IP.
- Restarted the NetworkManager service.
- Nothing seemed to happen.
- Logged out, logged back in (using the original IP.)
- Still works.
I guess restarting Network Manager doesn’t restart the interfaces.
$ ssh firstname.lastname@example.org [..] # ifconfig eth0 eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.221 netmask 255.255.255.0 broadcast 192.168.1.255 <snip>
It did. But hang on … the IP address is not the one I accessed the server with!
# ip a list 1: lo: <LOOPBACK,UP,LOWER_UP> <snip> 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 <snip> inet 192.168.1.221/24 brd 192.168.1.255 scope global noprefixroute dynamic eth0 valid_lft 863962sec preferred_lft 863962sec inet 192.168.1.247/24 brd 192.168.1.255 scope global secondary noprefixroute dynamic eth0 valid_lft 36515sec preferred_lft 36515sec <snip>
- It’s kept the old IP alive; I assume for the duration of the lease.
- A use case where ‘ip’ definitely trumps ‘ifconfig’. (old dog, new tricks)
- Not expected behaviour. Nice, but not expected.
Also: useful. Puppet is telling logging clients to use the old IP. I need a bit of time to push around the IP change: Network Manager has handled the transition for me.
Original plan was a static IP for logging. But I hoped to keep DHCP for the host, because it turns out Network Manager is getting configured much better with DHCP than it would with a static IP. The network manager module I’ve downloaded for Puppet isn’t as simple as it first looked, and needs some testing and investigation – so I’ve left that addition on the backlog.