VIRTUAL PRIVATE SOMETHING
I was fairly late to start playing with VPSs, though it seems I
started at a good time a few years ago because the similarly-priced
(ie. extremely cheap ~$1AUD/month) KVM VPS plans now mostly have
more limited specs. This has kept me with 1GB of RAM and 16GB
storage through a VPS offer which was downgraded just months after
I signed up for it it. What hasn't stayed with me is the one 'vCPU'.
Of course I still get a virtual CPU to do the work, but it's not
the one that I started with. Earlier this year the host advised of
a hardware issue with the RAID array of the physical server it was
running on, and as such they moved all users over to another
physical server. Actually they just made me a second VPS account
and left me a week to move things over myself before disabling the
old one, which did at least provide a handy opportunity to convert
the original host-provided Debian installation over to blissfully
Systemd-free Devuan and do a version upgrade, while the old server
was still running to host my websites.
But although the 'new' VPS had the same RAM and SSD storage, my
vCPU had changed:
Old:
model name : Intel(R) Xeon(R) CPU E5-2690 0 @ 2.90GHz
stepping : 7
microcode : 0x1
cpu MHz : 2899.998
New:
model name : Intel(R) Xeon(R) CPU E5-2695 v2 @ 2.40GHz
stepping : 4
microcode : 0x42e
cpu MHz : 2399.998
Still an old model Xeon processor, but a slower clock speed! Sure
enough, tests showed a corresponding reduction in processing speed
for one of my common CPU-bound processing tasks. So there goes my
assumption that the same VPS deal will get you the same or better
CPU performance forever, even if the advertised stats stay the same.
But at least the CPU stats have some relation to real performance
with that provider, I've found that the free VPSs that Oracle Cloud
offers are over-provisioned, so when you turn up the CPU load and
watch in Top, the hyperviser constantly steals a big chunk of
processing time away, making their 'oCPU' stats potentially
meaningless since you're not actually getting all of those CPUs to
yourself.
The other thing that happend with the move to the replacement VPS
was that the IP address changed, for the third time (last time
there wasn't even a transition period, I had to rush to reconfigure
my dead domains after getting the email). Also to again ask support
to also set its rDNS setting to the main domain name for the sake
of email (not possible in the 'control panel', contrary to their
documentaiton when I first signed up). Unfortunately this most
recent IP address, although fine by public blacklist checks, seems
to have been blacklisted by various big email hosts including
Microsoft, Apple, and AOL. So in spite of ticking all the boxes for
DKIM, SPF, DMARC, and rDNS, they suddenly started rejecting my
email outright. Microsoft (most important of the three due to all
the Hotmail addresses they control) annoyed me particularly because
the server rejection message didn't explain how to request removal
from the blacklist, so I had to find instructions here:
https://www.rackaid.com/blog/hotmail-blacklist-removal/
Then that required me to create a Microsoft account just to fill in
their blacklist removal form!
So the take away from my VPS experience so far has been that if you
want a predictable environment (especially to run a mail server)
you need to ditch the virtual, run on dedicated server hardware,
and buy your own IPv4 address/block to boot! So, as is to be
expected, it's all so much easier if you have money to burn. It's
just annoying that you have to experience these services yourself
to find out how they really work.
- The Free Thinker
