== Stretch to Buster Upgrade ==

Notes so far:

 * Upgrade needsrestart first and set NEEDRESTART_SUSPEND=1 to avoid be prompted to restart services (they will all be restarted on reboot)
 * `dpkg: error processing archive /var/cache/apt/archives/needrestart_3.4-5_all.deb (--unpack): unable to create '/etc/apt/disabled.apt.conf.d/99needrestart.dpkg-new' (while processing './etc/apt/apt.conf.d/99needrestart'): No such file or directory`. I think I got this message because I set the environment variable `NEEDRESTART_SUSPEND=1` before upgrading needrestart. I fixed with:
{{{
mkdir -p /etc/apt/disabled.apt.conf.d/
}}}
I should have fixed with unsetting the env variable and installing needrestart again
 * php curl packages seem to be removed on upgrade (7.0, 7.1 and 7.2), there seems to be some fundamental incompatibilities at play:
{{{
dpkg: dependency problems prevent configuration of php7.0-curl:
 php7.0-curl depends on php7.0-common (= 7.0.27-0+deb9u1); however:
  Version of php7.0-common on system is 7.0.33-0+deb9u5.
 php7.0-curl depends on libcurl3 (>= 7.18.0); however:
  Package libcurl3 is not installed.
 php7.3-common (7.3.4-2) breaks php7.0-curl (<< 7.0.33-1~) and is installed.
  Version of php7.0-curl to be configured is 7.0.27-0+deb9u1.
}}}
Are we going to have to force upgade everyone to php 7.3?
 * `doveconf: Warning: Obsolete setting in /etc/dovecot/conf.d/99-mfpl.conf:27: ssl_protocols has been replaced by ssl_min_protocol` (fixed via puppet)
 * `doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-ssl.conf line 13: ssl_key: Can't open file /etc/dovecot/private/dovecot.key: No such file or directory` (see [https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=867593 debian bug]) - fix with `ln -s /etc/dovecot/private/dovecot.pem /etc/dovecot/private/dovecot.key`
 * `Errors were encountered while processing: postfwd` but when I reran `apt install postfwd` it went through without error

== Prompted config files ==

 * /etc/logrotate.d/apache2: Do we still need our customizations of this file?
 * /etc/systemd/journald.conf: The new default file has some changes to commented out things... we should update ours to reflect the changes
 * /etc/systemd/timesyncd.conf: The new default file has some changes to commented out things... we should update ours to reflect the changes
 * /etc/cronttab: THe new default has helpful comments... we should update ours to reflect the changes
 * /etc/logrotate.conf: new defaults keep less logs around, we should update ours to reflect
 * /etc/ssh/sshd_config: I think we have already incorporated these changes
 * /etc/default/postfwd
 * /etc/default/spamassassin