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>> I'm about to embark on this (perilous?) journey and I'm wondering if |
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>> anyone would make a comment on any of the questions in the last |
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>> paragraph below. This is basically my plan for setting up a bunch of |
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>> systems (laptops) in an office which are hardware-identical to my own |
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>> laptop and creating a framework to manage them all with a bare minimum |
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>> of time and effort. |
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>> |
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>> Thanks, |
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>> Grant |
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>> |
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>> |
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>>>>>>>> I see what you desire now - essentially you want to clone your laptop |
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>>>>>>>> (or big chunks of it) over to your other workstations. |
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>>> |
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>>> I've been working on this and I think I have a good and simple plan. |
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>>> |
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>>> My laptop roams around with me and is the "master" system. The office |
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>>> router is the "submaster" system. All of the other office systems are |
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>>> "minion" systems. All of the systems are 100% hardware-identical |
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>>> laptops. All of the minions are 100% software-identical. |
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>>> |
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>>> I install every package that any system needs on the master and create |
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>>> an SSH keypair. The only config files that change from their state on |
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>>> the master are: /etc/conf.d/hostname, /etc/conf.d/net, |
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>>> /etc/ssh/sshd_config, /etc/shorewall/*. I write comments in those |
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>>> files which serve as flags for scripted changes. |
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>>> |
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>>> I write a script that is run from the master to the submaster, or from |
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>>> the submaster to a minion. If it's the former, rsync / is run with |
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>>> exceptions (/usr/portage, /usr/local/portage, /var/log, /tmp, /home, |
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>>> /root but /root/.ssh/id_rsa_script* is included), my personal user is |
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>>> removed, a series of workstation users are created with useradd -m, |
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>>> services are added or removed from /etc/runlevels/default, and config |
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>>> files are changed according to comment flags. If it's the latter, |
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>>> rsync / is run without exceptions, services are added or removed from |
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>>> /etc/runlevels/default, and config files are changed according to |
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>>> comment flags. |
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>>> |
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>>> All user info on the submaster and minions would be effectively reset |
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>>> whenever the script is run and that's fine. Root logins would have to |
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>>> be allowed on the submaster and minions but only with the SSH key. |
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>>> There are probably more paths to exclude when rsyncing master to |
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>>> submaster. |
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>>> |
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>>> That's it. No matter how numerous the minions become, this should |
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>>> allow me to keep everything running by administrating only my own |
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>>> system, pushing that to the submaster, and having the submaster push |
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>>> to the minions. I've been going over the nitty-gritty and everything |
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>>> looks good. |
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>>> |
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>>> What do you think? Is there anything inherently wrong with rsyncing / |
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>>> onto a running system? If there are little or no changes to make, |
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>>> about how much data would actually be transferred? Is there a better |
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>>> tool for this than rsync? I know Funtoo uses git for syncing with |
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>>> their portage tree. |
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>>> |
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>>> - Grant |
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>> |
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> |
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> Only thing that comes immediately to mind in rsyncing an overwrite of |
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> / is that any process that's running that goes looking for libraries |
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> or other data after the rsync pulls the rug out from beneath it might |
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> behave erratically, crash, kick a puppy, write arbitrary data all over |
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> your drive. Also, it's somewhat important to be careful about the |
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> various not-really-there mounts, /dev, /sys, /proc... /run's probably |
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> touchy too, and /var has a few pieces that might be in use mid-sync |
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> and choke something along the way. My idea on that would be... build |
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> an initramfs that: |
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|
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What if the push is done while no one is logged in to the system(s) |
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being updated? I could also exclude /dev, /sys, /proc, and /run and |
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reboot after the update. If that's not good enough, what if I boot |
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the systems being updated into read-only mode before updating them? |
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I'm hoping to keep the process as simple as possible. |
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|
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- Grant |
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|
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|
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> 1) boots to a script |
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> a) warns the user that it's hungry and that feeding it will be |
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> dangerous to any non-backed-up data, with prompt |
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> b) warns the user again, with prompt ('cause watching an rsync roll |
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> by that eats that document you just spent 3 weeks on isn't fun) |
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> 2) mounts / in a working directory |
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> 3) rsyncs the new data from the sub-master |
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> 4) kicks off a script to update a hardware keyed (mac address is good |
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> for this) set of settings (hostname, etc) |
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> 5) reboots into the new system. |
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> |
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> For extra credit... sync /home back to the sub-master to prevent |
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> overfeeding the beast. |
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> |
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> -- |
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> Poison [BLX] |
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> Joshua M. Murphy |