System Maintenance Today, Downtime

I take the somewhat unusual approach, Of hosting this Web-site, and therefore also my blog, on my personal computer at home. Therefore, any downtime of my home computer, also affects the visibility of the blog. And, as long as the actual Web-server is not online, I also cannot make it display a maintenance-mode page.

Just in recent days, I took the more-unusual step, of running the command:

 


root@Phoenix:/home/dirk# update-initramfs -u -k 3.18.0-14-generic

 

What was unusual about this, was the fact that this was not the command:

 


root@Phoenix:/home/dirk# update-initramfs -u -k 3.16.0-4-amd64

 

While it seemed nice for some time, to be running a kernel-version named ‘3.18.0-14-generic’, the mainstream version which a Debian / Jessie system is supposed to be running, is ‘3.16.0-4-amd64′. So, while the mainstream kernel had been receiving regular updates, I was running a kernel, which had not been receiving any updates, for years now. This helped reduce the number of reboots which I needed to carry out, due to frequent updates on the ‘3.16.0’ kernel.

But just because this was the first time in ages, that I had run the ‘update-initramfs’ command on the running kernel, I next needed to attempt a reboot, just to see whether the computer could still boot.

Therefore, readers would have experienced problems accessing my blog or site, from about 16h40 until about 17h10 today.

And No, My system Failed to Reboot.

Continue reading System Maintenance Today, Downtime

Future Downtime

I host my Web-site, and therefore also my blog, on my own server at home – i.e. using my home connection to make this site visible to readers.

This makes me susceptible to power-failures, which would cause this site to be unavailable temporarily.

I’m also a customer of the power utility named “Hydro-Quebec”.

Hydro-Quebec has just given me a courtesy call, according to which they have scheduled work to be performed on the power-lines in my neighborhood, due to which a planned power-cut is to take place, on Tuesday, July 18, 2017, “from 12h30 until 15h30″.

In anticipation of this power-cut, I will actually be shutting down my computers, to avoid any danger of file-system corruption. Therefore, my site will not be available around that time.

I apologize in advance, to any readers who may find this to be an inconvenience.

Dirk

 

My P2P Bitcoin Core Client taking a vacation today.

Today is Friday, July 7, 2017. According to some weather reports, there is a risk of Thunderstorms today. As I’m writing this the time is only 14h30 or so, and the Thunderstorms are expected for maybe around 17h00 or so.

A Thunderstorm could knock out my power, and could cause my blog to go offline. But this is a relatively minor inconvenience, according to recent experiences, because eventually I’d be able to reboot the host-machine and thus make the blog available to readers again.

If I had a Bitcoin P2P-client running, a power-failure could have more serious consequences.

So just to be safe, I shut down my Bitcoin P2P-client program for the day, while my Web-server is still running. I figure that providing no service for the time being, is a better alternative, than providing service which has gotten corrupted in some way. And then there could also be the eventual risk, of my having to rebuild my local copy of the block-chain, if simply rebooting the host-machine fails to recover it.

Because there are no T-Storms forecast for Saturday, I expect just to restart my P2P-client on Saturday morning. Sorry for any inconvenience to Bitcoin users today.

(Edit : )

As of 20h30, I am back up. For the moment, the Thunderstorm that was forecast, did not seem to materialize.

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.