Mail Server Replacement

     I am going to replace the existing Centos6 based system powering with a brand new Ubuntu 19.10 based system.

     This brings with it immediately only some minor benefits, new stronger key exchange methods for key exchange for example.

     In the longer term it will also bring better spam and virus filtering.

     Because I’ve had this new server on a different hostname and IP address getting it ready, I will need to take the old machine down and then change the hostname and IP address of the temporary name to

     In addition because of changes in the ownership convention between CentOS6 and Ubuntu, I will need to change the owner on all the list files.  This may take some time so mail lists may be out of service for an hour or more.

     During this interval you will not be able to send mail and you will only be able to read mail via non IMAP based shell mail programs.



     I will be rebooting all Intel-based servers later this evening or very early Saturday morning (near midnight), in order to load new kernels that address yet another newly discovered Intel exploit.

     When I recompiled the client mail server the day before yesterday, it overwrote the existing aliases file breaking all aliases and mail lists.  This has been fixed.

     If all goes well, and it hasn’t the last two nights, I hope to replace the client mail server, currently based upon Centos6, with a new mail server based upon Ubuntu 19.10.  This will come with some newer spam tools that hopefully will result in fewer abuses like the forgery from alleging that your mail quota was full.


     At some point, Canonical, the folks behind the Ubuntu Linux distribution that we use on most of our servers, opted to move where firewalld looks for iptables, iptables-restore, ip6tables, and ip6tables-restore from /sbin to /usr/sbin but neglected to move the actual commands there, thus causing firewalld to fail upon startup.  And rather than no firewall being started it seemed to result in random ports being blocked.

     This condition broke the ftp server so that it would not function in active mode and sometimes not even in passive mode.  This has been repaired.

     If you are sitting behind NAT on a personal home router and do not have a static IP, you still may need to use passive mode but at least that will work now.

     I also want to remind people that IF you have a public incoming or uploads directory, the mode must NOT offer public read permissions or it will not work.  Our ftp daemon will not allow the use of mode 777 directories since this is used and abused to distribute viruses, pirated software, child porn, and other nefarious content.  Instead these directories should be mode 733, chmod 733 incoming.

Sending Mail Fixed should be completely fixed now but I will be replacing it entirely shortly as it is an old server based upon CentOS6, the only one not modernized, and I am preparing a new server to completely replace it which will be based upon the current release of Ubuntu and upgraded as Ubuntu upgrades.

      In the meantime however, I have replaced postfix with the most current version, 3.4.7, as well as openssl with 3.0.0, so all modern encryption protocols should now be supported.

Sending Mail – An Update

     Authentication was broken, that is now fixed.  Sending mail will work from local shell servers, from web mail, but NOT from devices off of our local network with encryption.

     I am working on fixing this but unfortunately it is somewhat involved so will take a little bit yet.

Sending Mail – Postfix

     I have discovered that what happened is that last night I recompiled postfix in order to add a needed feature to make it work in some situations that previously it did not.  I was missing a necessary library on the system when I first compiled it and this caused it to omit adding that feature.

     What I did not realize at the time was that installing the newly compiled version would rudely overwrite my existing configuration files.

     I can not boot the backup because init, the master daemon is damaged.  So I am trying to extract the configuration files from the backup.