Apache Update Today

I take the unusual measure of hosting this site, and this blog, on my home computer, which I name ‘Phoenix’. This requires that I forward all requests to my URL, to My Home IP Address. Hence, if you’re on a Linux computer and want my current IP address, you’d just type in:

 


host dirkmittler.homeip.net

 

But of course, in order to host a Web-site, I also need to be running a fully-configured Web-server. Under Linux, this pretty much implies running Apache.

The version of Apache on this box was just updated this evening, to version ‘2.4.10-10+deb8u10‘. When the server is updated like this, a post-install command is also given to restart it, since otherwise the new software will not have been loaded into RAM, nor running. But this should not cause much of a disruption, because essentially it just causes a connection to disappear for about 2 seconds.

The reason for that would be, the fact that each HTTP Request is handled separately, and after each HTTP Request has fetched a page, or an update to a page, the CGI-Script that did so exits. This means that if the reader is noticing a ‘stateful session’, which has persistent data from one page-reload to the next, this actually requires that a database act as a back-end to the site, and that the Web-server’s CGI-Scripts can act as a client to that database. And cookies on the browser, in certain cases, identify a session. For readers of this blog who are not logged-in, such cookies are not being used.

In my case, it’s a MySQL server.

One thing that might however happen to a reader, due to such a server-restart, is that an established session gets interrupted momentarily. This would have happened around 19h45 this evening.

The reason that can happen, is the use of Web-sockets on this site. Essentially, only the browser’s initial request to connect, is actually made to Port 80 of the server. After that, the session of one particular browser (client) is handed off to a Web-socket, which is actually some obscure port on my computer, owned by an Apache sub-process.

If the sub-process is killed, any browsers that were still connected to it would have experienced a disconnection. Because browsers tend to ‘remember’ which Web-socket they were connected to when simply prompted to reload a page, this disconnection might last until the reader restarts his browser.

Continue reading Apache Update Today

Routine Apache Server Update Today

One fact which I mention often, is that I use my home computer, which I name ‘Phoenix’, as a Web-server, and as the hosting server for this blog.

For any readers who have questions on how this is possible, I’d direct you Here.

Updates which are somewhat remarkable, such as an actual update to the Web-server, but which seemed to take place without any technical problems, I document in this blog as ‘routine updates’.

The update to my Apache Web-server, that brought it up to version ‘2.4.10-10+deb8u9‘, just took place today. Doing so actually does require a restart of the server. But that kind of restart simply takes place within a few seconds, and without any detriment to the availability of the site, because of the way Web-servers generally work.

Dirk

 

Major Upgrade This Evening, Downtime

Both the Linux-laptop I name ‘Klystron’, and the server of this Web-site, this server being named ‘Phoenix’, received a major update this evening. On ‘Phoenix’, a total of 78 packages needed to be updated, including a Kernel-Update, and a Graphics-Driver Update. This collective update effectively converted both computers from Debian 8.7 to Debian 8.8 systems. And both updates appear to have succeeded, at first glance without breaking anything.

However, this was an update that required a reboot for ‘Phoenix’, even though this is my Web-server, and so my site was also down briefly, from approximately 20h40 until 20h50.

I am happy to say however, that ‘Phoenix’ had been running for 58 days straight, without requiring any reboot whatsoever until tonight.

Oh, but I must disappoint some of my readers with the fact that performing these updates also required I restart my ‘memcached‘ service, which means that pages or postings the readers like to visit most often will be a bit slower to fetch, until this server-side caching is replenished.

Dirk