No Internet for Old Computers                              2022-10-30

Well, it lasted about a week hosting a web site and gemini capsule on
the Sun Blade 100. Although only a handful of people visit here, the
500MHz UltraSparc IIe CPU was no match for bots, and floods of
automated requests from Mastodon servers.

Both gemini and any sane website really need to be using TLS 1.2 or
above, with good ciphers and large enough key size. Modern low power /
low spec embedded systems of comparable general compute ability to the
21 year old UltraSparc tend to have acceleration of the encryption
mathematics. This means you can host an https site on something really
low spec, but it can remain fairly responsive. There's no such luck on
the Sun Blade. It just has to slowly churn through the
encryption/decryption code, and takes about 1-2 seconds to handle a
request.

I didn't anticipate this being an issue, but I'd forgotten (again)
about the prevalance of badly coded bots in the gemini space, plus the
DDOS style web link fetching of Mastodon.

The gemini server was getting periodically strained by what I can only
assume are some first time experiments in writing crawlers. More than
a few examples seen of IP addresses repeatedly slurping as much as
they can, with no rate limiting, and often needless duplication. On
the web server side, linking from Mastodon, in a post or from my
profile, leads to a sudden onslaught of requests as each server that
federates with mine fetches the same link.

A few humans browsing at a time is fine for the Sun. 65+ Mastodon
servers trying TLS connections all at once is not. I could do rate
limiting and blocking, but blerghh... that quickly turns this from a
bit of fun into somethin that's a lot like work.

The web site and gemini capsule are back to a small, but modern, VPS
instance... and are plenty speedy now.