One master, two slaves running CentOS 6.2 update successfully. Hi, This was the first time I used the update process. As someone already posted, the update process hangs after starting mailman. If at that point (in another shell) you stop the mailman service with "service mailman stop", the update process resumes after a few seconds. A couple more services restart and the update is finished. (At which point you of course need to restart the mailman service.) A more annoying problem I had was with my SSL certificates: - I have some "real" certs for the ispconfig site, but the ispconfig.vhost file was overwritten. I needed to put the original file (content) back. - All three of the installes run a postfix mail server with "real" SSL certs. Sine the main.conf file was overwritten, those needed to be put back manually too. Not sure how you would be able to fix these issues since these certs cannot be entered into the ispconfig interface (please correct me if I am wrong). Even for the ispconfig vhost, putting the certs in the default location does not work since I need to add a certificate chain bundle file and the default vhost file only hase the cer and key files entered. But all in all these issues are minor and easy to fix (using the automatic etc backup) so I am totally happy with the product and the update process. Thank you for the awesome product. Anset PS. For those who do not have the manual yet; it's totally worth the small purchase price!