libc Updates today, Downtime

This computer is a Debian / Jessie (Linux) system. Just today, it mainly received an update to its ‘libc‘ libraries, that comprised 16 packages. These libraries are essential to the core of how every program works. Therefore, even though it is a Linux system, it needed a reboot.

The update seems to have gone smoothly, but because this computer is also my Web-server, my site and blog would have been offline from about 20h30 until 20h45.

It is also not feasible for me to display a Maintenance Mode page during such a time, because a Web-server would need to be running, in order actually to display a Maintenance Mode page.

I apologize for any inconvenience this 15-minute interval may have caused to my readers, but it was essential.

Also, because this was a full reboot of my host-machine, my ‘memcached‘ (server-side) caching daemon was restarted, for which reason the most-favorite postings retrieved by my readers will be a bit slow to fetch for some time.

Sorry again,

Dirk

 

Power Fluctuations, Downtime

I take the unusual step of hosting my Web-site, and this blog, on my personal computer at home. If the reader has questions about how this is possible, I gave a brief explanation here.

One of the unfortunate facts which this implies, is that my site availability is only as good as the reliability of my personal computer. People who have their sites hosted more conventionally on professional services, are also paying to have professionals avoid downtime.

Today we are having extreme weather on the Island Of Montreal. The maximum daytime temperature is expected at 32⁰C, and we are having continuous, powerful wind-gusts.

What this has done is cause brief, momentary power-fluctuations to take place, that are long enough to cause this hosting computer (‘Phoenix’) to go down, but which are short enough, that the supply-capacitor charge on most of my other systems – including several other computers – allows those to keep running, as though no fluctuation had ever taken place.

In fact, this has taken place in such a way, that my IP address never actually changed. But, my Web-server ‘Phoenix’ did go down, not once but twice so far, taking my Web-site down with it.

This started happening around 12h00 today, but is expected to continue throughout the afternoon. The extreme weather is in fact expected to break, when severe Thunderstorms put an end to the high temperatures.

Also, because this type of a reboot causes my server-side caching-daemon ‘memcached‘ to restart, it means that the speed with which the most-frequently-requested pages are served, will be slow for some time to come.

I apologize to the reader for this, but it is just an automatic hazard that follows, when we host our Web-site on our home computers.

Dirk

(Edit: )

This type of a ‘power fluctuation’ can be described more precisely. One seemed to take place which I did not witness, while one took place which I did.

I’d call that one a ‘voltage drop-out, that lasted somewhere between 1/10 and 1/5 second’. There seemed to be no period of partial voltage; the lights just went dark for that fraction of a second.

 

WordPress Debian Update Today

I use a version of WordPress to host my blog, which is very similar to the versions offered by WordPress.org, but which have been tweaked by Debian Developers, to add security, as well as to increase compatibility with Debian Linux.

But, it’s my personal habit to operate this platform with the ability to install plugins and Themes from the WordPress.org site. Making this available involves some trickery with symlinks and with directory ownership. Yet, WordPress itself is designed with flexibility in mind, when it comes to local configurations. So it tolerates this as a platform.

But from time to time, Debian Maintainers push through an update to their core version of WordPress – which I am using. I happen to have my core files installed in ‘/usr/share/wordpress‘, while I have my extensions installed in ‘/var/lib/wordpress/wp-content‘. The permissions and ownership for these two directories, as well as their subdirectories, involves two different settings in my configuration. One directory, with all its subdirectories, is not writable by the Web-server, while the other is.

When Debian Team pushes through one of these updates, it can break how my personal localization works, because Debian Team is inherently unaware of how any systems may be configured, which are not Debian. This is a bit like how Microsoft programmers inherently don’t understand anything which is not Microsoft.

Sometimes I have installed the update to the core files, without any issues, but sometimes, some additional, manual work is required on my part, to ease the update.

This afternoon, the core files installed fine, and left me with a working blog. But there exist some Themes and plugins which need to be installed from the package manager, to ensure a working site, but of which I usually have the latest versions, from WordPress.org instead. The packaged versions of these Themes and plugins generally tend to lag behind, the most up-to-date versions from WordPress.org.

This means that after one of the core updates, I typically need to reinstall the update, to whatever Themes and plugins the package-manager update has rolled back.

This morning, that added step in my procedure ran into some trouble. But, I was able to resolve the issue in little time, and my blog seems to be at 100% again.

Now, I do have a plugin which puts up a Maintenance Mode page, for as long as I like. But generally, I find that this plugin only hinders me. For one thing, if some type of mess results on my hard drive, having this page enabled could prevent me from disabling it again, and from fixing the issue. Secondly, whatever maintenance I do, is generally finished within 15 minutes or so. So I generally don’t use this plugin.

This afternoon, I began by allowing the core update to take place around 13h30, at which point the blog was still displaying fine. But I ran into issues getting the “TwentyFifteen” Theme back up-to-date, which would have caused any readers to see artifacts when trying to view my page, which were all gone and repaired by 13h45.

So for 15 minutes, readers might have seen some artifacts. If you did, I truly apologize. If I had used the Maintenance Mode plug-in, then doing so would have made my manual procedure more complicated, so that you might have seen the Maintenance Mode page instead, all the way until 14h00. In other words, the task could have taken twice as long to complete than it did.

My official WordPress version is now ‘4.1+dfsg-1+deb8u14‘. And it works again.

Dirk

(Edit: There exists a phenomenon in Human Psychology, with a name I forget. Essentially it amounts to stubbing one’s toe on a table-leg, and due to the unexpected or even inconvenient timing of the pain, blaming the table-leg for the accident. In retrospect, now that this pain is gone, I’d say this SNAFU was entirely my own fault.

Continue reading WordPress Debian Update Today

Power Failure, Downtime

This morning as I slept, the power to my home went off around 3h05.

Because this home-computer, which I name ‘Phoenix’, is also my Web-server, that means that my site and my blog were also offline from about 3h05 until 3h35.

This power failure may have been caused partially, by this exceptional weather situation, previously mentioned.

I apologize to any potential readers, for whatever inconvenience this may have caused you.

Also, since any reboot also restarts my ‘memcached‘ daemon, again the retrieval of certain postings will be slow, until the server-side cache is replenished.

Dirk