I'm switching my laptop from VMWare to VirtualBox (basically cloning the already working version from my desktop, which has things properly set up for email, etc) -- and ran into issues with networking. And at first I thought it was because I hadn't set up dnsmasq properly, or that it was this old issue with setting up dhcp that I vaguely remembered having to deal with the first time.
But after fixing all that, still nothing. And uh. It turns out the solution was to rename the interfaces from eth0/eth1 to eth4/eth5.
I have no idea what just happened, other than that my computers have decided that it's fun to mess with me.
(I think the main reason I'm leery of sysad stuff is that every time I come back to edit something, I have to basically start from scratch. I should try to figure out how to easily document my actions when I work on the sysadmin side of things, so I can find out what I just did, two months from now.
It's really easy for code, e.g.,
git stash, but the same trial and error approach I do for code just leads to confusion when I try to remember what I just did when it comes to working on my system...)
(I'm beginning to think that the other reason I find sysadminning so hard is that I only rarely can figure out from the instructions which parameters are arbitrary, and which parameters must be based on values from your system. For instance, in:
VBoxManage dhcpserver add –netname (the internal network name e.g. intnet) –ip <your RFC 1918 address> (e.g. 192.168.x.x, 10.x.x.x, 172.16.x.x)\ –netmask <your subnet mask> (e.g. 255.255.255.0) –lowerip <your lower IP range> (e.g. 192.168.1.2) –upperip <your upper IP range> (e.g. 192.168.1.254)
- --netname is arbitrary
- --ip is sort of arbitrary, but I thought it had to be based off an already assigned ip address
- -- netmask is always just 255.255.255.0 for my purposes
- --lowerip/--upperip are arbitrary, but since I was confused about --ip before...
Also in the GUI, there's an adapter IP and the DHCP server IP, and it's not clear whether the --ip is for the former or the latter. It turns out it's the former, but good heavens how do people know? I basically had to plug in reasonable-seeming values and restarting stuff to test, with the only feedback being that it either failed or succeeded, and no way of telling which of the inputs was the reason for the failure, or if it was none of those.
UGH. Not my favorite thing in the world.)