Upgrading 11.2 -> 12.0 on EC2

[Matt Garber]

> On Dec 19, 2018, at 1:50 AM, Brian Neal <brian at aceshardware.com> wrote:
> 
> I’m looking for advice on doing a release upgrade of a running instance.  It looks like the normal procedure using freebsd-update requires a reboot between invocations of the install command, but after the first reboot, most of the userland is non-functional, including most importantly sshd. Is it safe to run the install commands back to back without rebooting?  Or is the only safe procedure to build a new instance from scratch for each release?

Brian,

It’s not true that after the first reboot the userland is non-functional; sshd and friends should still be working fine. The first reboot switches you to the 12.0 kernel, which is necessary as the first step before upgrading the userland to 12.0 – and of course potentially using `pkg-static` or ports to rebuild/reinstall your packages/ports against the new ABI.

If you’re running any kind of public-facing service, the safest method in my opinion *with as little downtime as possible* is to deploy a new instance and then point to it once everything is successfully reinstalled (e.g., DNS change, elastic IP change, elastic load balancer, etc.). Otherwise, the “safe” method to upgrade in place is to follow what the handbook says, including when to reboot between invocations of `freebsd-update`. As long as you follow exactly when it instructs a reboot, and when to upgrade/reinstall userland and packages/ports, you should be fine. If you’re still nervous, just snapshot your boot EBS volume first as an extra precautionary measure, and destroy it once you verify everything post-upgrade.


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Matt Garber