==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.7
- Linux/BSD distribution name and version: Debian 9
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): Mariadb
- Web server (Apache or Nginx): NginX
- Manage mail accounts with iRedAdmin-Pro? nop
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

hello !

I've used 2~3 years ago the 0.6 version of iRedMail, and I've done some modifications in config files to be customized like I would. So, I've never upgraded Debian or iRedMail because I was afraid to break something, but I known it's not a good idea for security reasons.

Few days ago, I've installed from scratch the 0.9.7 and imported previous emails, now all is good, debian is up to date, and my config are still customized like I need.

So, my question is, is it safe to manually upgrade the debian server ( apt-get upgrade ) without breaking anything ?
Or do I need to wait announces on the mailing-list of iRedMail to upgrade the server on the same time than a new version of iRedMail is released ? (or may be the upgrade of iRedMail also upgrade the system?)

Thanks for your informations and this amazing project!