We now have a Dockerfile to serve the upcoming https://k-v.io.
The dockerfile is patterned after the sslip.io nginx Dockerfile.
Note: the content isn't ready; the HTML needs fleshing out.
Also includes a gratuitous change to the HTML in order to trigger a
build.
Fixes <https://ci.nono.io/teams/main/pipelines/dockerfiles/jobs/build-and-push-sslip.io-nginx/builds/33>:
```
error: failed to solve: rpc error: code = Unknown desc = executor failed running [/bin/sh -c dnf install -y bind-utils iproute less lsof neovim net-tools nginx nmap-ncat procps-ng RUN mv /usr/share/nginx/html /usr/share/nginx/html-orig]: exit code: 1
```
The original behavior was to return the deleted record, which
inadvertently prolonged the lifetime (in DNS cache) of the record which
was meant to expire as soon as possible.
- Removed the instructions to create a BOSH release. We are no longer
creating a BOSH release because we needed to colocate an etcd release
alongside the BOSH release, and we couldn't find an etcd BOSH release.
- Updated the instructions to run a quick test against the sslip.io DNS
server locally (sanity check) instead of deploying a VM with the BOSH
release & testing against that.
- Updated the instructions for updating ns-azure's DNS server. ns-azure
is no longer a BOSH-deployed VM.
- updated comments in `blocklist.txt` to include references to CIDRs &
how they're handled
- updated webpage to include description of the upcoming metrics for the
blocklist
Also, I moved the "versio" endpoint: `version.sslip.io` →
`version.status.sslip.io`. It seemed to make more sense to corral the
special endpoints under `status`.
- The metrics aren't fleshed out. In fact, there's only two so far:
1. uptime
2. number of queries
- Even though the metrics aren't complete, I'm checking it in because
this commit is already much too big.
- I moved the version information to `version.status.sslip.io`;
previously it was at `version.sslip.io`. I didn't want one endpoint
for both metrics & version (worry: DNS amplification), and I wanted a
consistent subdomain to find that information (i.e.
`status.sslip.io`).
- I'm not worried about atomic updates to the metrics; if a metric is
off by one, if I skip a count because two lookups are happening at the
exact same time, I don't care.
- The `Metrics` struct is a pointer within `Xip` because I might have
several copies of `Xip` (if I'm binding to several interfaces
individually), but I must only have one copy of `Metrics`
- I only include the metrics I'm interested in, usually because it took
some work to implement that feature. I don't care about MX records,
but I care about IPv6 lookups, DNS-01 challenges, public IP lookups.
- got rid of a section of unreachable code at the end of
`ProcessQuestion()`; I was tired of Goland flagging it. I had it there
mostly because I was paranoid of falling through a `switch` statement
I didn't want a really long domain for the key-value store; I wanted a
short, easy-to-remember domain. And it cost $400 for ten years.
Many good domains (e.g. keyvalue.store, kv.io)
were taken, and some weren't easily registered (e.g. the Albanian
domain, keyv.al).
Browsing these domains that were never put into use is like strolling
along the Boulevard of Broken Dreams: high hopes dashed against the hard
rocks of reality.
We set the number of replicas to 1 so that when you create a key-value
on `ns-gce.sslip.io`, you're sure of retrieving that value later from
`ns-gce.sslip.io`.
Previously it could hit the other replica, which would have a different
key-value store, which would make the value "disappear".
We enable special behavior under the `kv.sslip.io` subdomain: it can be
treated as a key-value store, the sub-subdomain being the key, and the
TXT record being the value.
For example, to write ("put") the value "12.0.1" to the key
"macos-version" on the `ns-gce.sslip.io.` nameserver, you'd use the
following `dig` command:
```shell
dig @ns-gce.sslip.io. txt put.12.0.1.macos-version.kv.sslip.io.
```
To read ("get") the value back, you'd write the following `dig` command:
```shell
dig @ns-gce.sslip.io. txt get.macos-version.kv.sslip.io.
```
Since "get" is the default behavior, you don't need to include it in the
domain name:
```shell
dig @ns-gce.sslip.io. txt macos-version.kv.sslip.io.
```
Finally, when you're done with the key-value, you can "delete" it:
```shell
dig @ns-gce.sslip.io. txt delete.macos-version.kv.sslip.io.
```
Notes:
- Keys are case-insensitive (to accommodate DNS convention). In other
words, `KEY.kv.sslip.io` and `key.kv.sslip.io` return the same TXT
record.
- Values are case-sensitive. `put.CamelCase.style.kv.sslip.io` sets the
TXT record to "CamelCase".
- `put` requests will return the TXT record being put; i.e.
`put.hello.world.kv.sslip.io` returns one TXT record of one string,
`hello`.
- `delete` requests will return the TXT record being deleted; i.e.
`delete.world.kv.sslip.io` returns one TXT record of one string,
`hello`. If the TXT record does not exist, no TXT records will be
returned.
- Values are limited to 63 bytes to mitigate using the sslip.io servers
in a [DNS amplification
attack](https://us-cert.cisa.gov/ncas/alerts/TA13-088A).
- Values are not persistent: if the server is restarted, all values
disappear. Poof.
- Values are not consistent. If a value is set in `ns-aws.sslip.io`, it
does not propagate to `ns-gce.sslip.io` nor `ns-azure.sslip.io`.
Our documentation was wrong; our homepage said to get the origin IP
address by querying the TXT record of the root, i.e. `dig
@ns-aws.nono.io txt . +short`; however, our code worked differently: it
returned the origin IP when the `.ip` TLD was queried.
The new behavior is that it returns the origin IP when `ip.sslip.io.` is
queried, and the documentation now reflects that behavior.
Also, that behavior is marked "experimental" to give us leeway to
change.
[fixes#11]
- Returns version information for DNS server
- Contains 3 strings:
- Semantic version, e.g. "2.2.1"
- Date of compilation
- Latest git hash
Note: the BOSH Release will have a different compilation date &
different git hash than the released executables; the semantic version
will be the same.
- Much of the information was from this blog post:
<https://goglides.io/manage-ntp-using-kubernetes/90/>
- Curiously, it creates another load balancer, so this brings me up to
three load balancers (HTTP(S)/DNS/NTP)
- It uses the OpenNTPD server. And ns-aws uses NTPsec, and ns-azure uses
the granddaddy, NTP.
We only have 1 node (because I'm frugal), so we really need only one
replica (it's more likely that the node has crashed rather than my
fairly-simple server).
Also, I pushed out the liveness probe to 5 minutes so the logs aren't
cluttered with probes every ten seconds.
I got rid of the readiness probe, which is only for "[applications
[that] are temporarily unable to serve
traffic](https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-startup-probes/)".
It cluttered the logs with its probes. Also my app is never
temporarily unable to serve.
fixes too many occurrences of:
```
::1.55268 TypeA 127.0.0.1.sslip.io. ? 127.0.0.1
```
