Web Server Caching

     I want to serve as much content out of memory as possible because you can’t get faster than that.  Google’s pagespeed module did not play nice with suexec or phpexec so I had to take that back out.  Memcached also occasionally corrupted pages, so got rid of that.  Now what I’ve done is created an in memory file system and used apache file caching.  Please notify support@eskimo.com if you see any bad behavior like corrupted css files.

Web Server

     Sorry for the somewhat flakey operation of the web server today.

     I tried to implement two different server optimizations, Apache’s caching in concert with memcached.  This mostly worked but occasionally corrupted pages so I had to back it out.

     Then I tried to run mod_pagespeed, a Google Apache optimization module, but it did not peacefully co-exist with provisions we use to run dynamic code under the user id of the user that owns that code resulting in all sorts of random permission errors.  So ultimately I had to back that one out as well.

Julia

     The programming language Julia is now available on all of our shell servers.  This language can be interpreted (with just in time compiling), or compiled to object.  It has a syntax in many ways similar to C++ but has a much more extensive set of math operations.  It can handle complex and imaginary numbers for example.  It also has nicer string operations than C or C++.  It has built in regex capability.  All in all it’s a very impressive language and worth checking out.

     It is also on our web server so you can use it for CGI’s if you like.

Server Reboots

     I will be rebooting our host servers tonight (physical machine) which will interrupt all of the guess servers (rebooting many of them) after midnight tonight.  This may take several hours during which you will experience interruption of services up to 1/2 hour.

     This is necessary to boot current kernels that have fixed various bugs and security issues.  Unfortunately the systemd scripts for Ubuntu are still someone buggy so sometimes it takes 3-4 attempts for a boot to succeed.

 

Pop before SMTP

     As you know, I recently replaced the old CentOS 6 based mail servers with new Ubuntu 17.04 based servers which allowed the implementation of new spam control facilities.

     I am now working on replacing the client mail server that provides pop3, imap, and smtp to customers mail clients.

     The old server supported pop-before-smtp for outbound mail. I will be unable to continue to provide this with the new server. Therefore, it will be necessary to configure your e-mail client to use authentication (plain password which is okay because you should also use TLS which will encrypt the entire session) for outbound SMTP mail.

     Some very antique versions of Eudora do not support this. These would have mainly been used on Windows XP and earlier systems. In this case you will need to upgrade to a more modern mail client, I recommend Thunderbird.

     I have several reasons for wanting to upgrade the outgoing mail server, the most urgent being is that the current outgoing server uses different locking methods than the new incoming server and this occasionally causes the Bayesian filters to get “stuck”.

     Secondary reason is that it will allow the installation of software that will provide MS-Exchange compatible services such as contact, and calendar services. This will mostly be helpful for people using Outlook.

     Lastly it will allow better virus filtering on outgoing mail, reducing the potential for a customer who has a virus in their system from spreading that virus to other customers.

Emergency Network Maintenance

     Isomedia is our co-location provider.  They provide an equipment rack in which our equipment is housed in a controlled temperature, humidity, and dust environment along with network connectivity.


ISOMEDIA will performing emergency network maintenance on 09/28/2017 at 12:00AM PDT to 04:00AM PDT. During this window, there will multiple periods of increased latency and packet loss, as network protocols re-converge.These periods may last between 5 and 15 minutes.

All times are estimates based on expected outcomes of the work being performed and previous experience performing the same or similar work. There is always the possibility of some unforeseen bug, or problem, that could extend the maintenance time or cause a disruption in connectivity. Administrators will make every effort to correct the problem, or implement the back out plan quickly, if something does occur.

We apologize for any inconvenience this work may cause.

Emergency Network Maintenance at Isomedia (where our equipment is co-located)

ISOMEDIA will performing emergency network maintenance on 09/12/2017 at 12:00AM PDT to 04:00AM PDT. During this window, there will multiple periods of increased latency and packet loss, as network protocols re-converge.These periods may last between 5 and 15 minutes.

All times are estimates based on expected outcomes of the work being performed and previous experience performing the same or similar work. There is always the possibility of some unforeseen bug, or problem, that could extend the maintenance time or cause a disruption in connectivity. Administrators will make every effort to correct the problem, or implement the back out plan quickly, if something does occur.

We apologize for any inconvenience this work may cause.

Client Mail Server Again

     The client mail server locked up again as far as Network I/O goes.  I suspect this is a kernel problem but I don’t have any good options for this server as newer kernels don’t work correctly with the antique version of glibc on this machine and older kernels have a security exploit.

     I am continuing to work on a replacement server based upon Ubuntu so it will have current everything.  I’ve got most of the software installed, but still working on the configuration of dovecot and postfix which is not straight forward, especially in the case of postfix because it operates in a very different environment.  Under Ubuntu, it operates within a chroot jail, this provides additional security but requires changes to paths and other configuration items.  I hope to get it operational this weekend.

Client Mail Server

     The client e-mail server, mail.eskimo.com, which provides imap, pop3, and smtp for clients and for webmail, stopped talking to the network sometime last night.

     It has been rebooted and is now operational again.

     I do not know what is causing it to do this but it is an old centos6 machine that I am in the process of configuring a new server based upon ubuntu 17.04 and the latest versions of all the software to replace the centos6 machine.

     Centos6 does not get maintained well by RedHat which is why I moved the incoming servers to ubuntu17.04.  Configuring this server takes longer because there are more software systems involved but I am getting close.