Many README files and other docs contained a link to a an appspot
tracking app that is no longer active. Following the links leads to an
error about Go 1.9 no longer being supported. Go 1.9 support was dropped
in appspot in 2019 and disabled June 2020.
This also resulted in a broken image link displaying when viewing these
files on GitHub. Since the app is no longer functioning, and since it
causes a potentially (but granted, minor) confusing error to display,
this just removes those links as I don't believe they are needed
anymore.
Signed-off-by: Sean McGinnis <sean.mcginnis@gmail.com>
[stackdriver addon] Bump prometheus-to-sd to v0.5.0 to pick up security fixes.
[fluentd-gcp addon] Bump fluentd-gcp-scaler to v0.5.1 to pick up security fixes.
[fluentd-gcp addon] Bump event-exporter to v0.2.4 to pick up security fixes.
[fluentd-gcp addon] Bump prometheus-to-sd to v0.5.0 to pick up security fixes.
[metatada-proxy addon] Bump prometheus-to-sd v0.5.0 to pick up security fixes.
Fix three issues with the fluentd-gcp liveness probe:
h1. STUCK_THRESHOLD_SECONDS was overridden by LIVENESS_THRESHOLD_SECONDS
if defined
Probably a copy/paste issue introduced in edf1ffc074
h1. `[[` is [a bashism](https://stackoverflow.com/a/47576482), and will always failed when called with `/bin/sh`
Introduced by a844523c20
Given that we call the liveness probe with `/bin/sh`, we cannot use the
double-bracketed `[[` syntax for test, as it is not POSIX-compliant and
will throw an error.
Annoyingly, even through it prints an error, `sh` returns with exit code 0
in this case:
```bash
root@fluentd-7mprs:/# sh liveness.sh
liveness.sh: 8: liveness.sh: [[: not found
liveness.sh: 15: liveness.sh: [[: not found
root@fluentd-7mprs:/# echo $?
0
```
Which means the liveness probe is considered successful by Kubernetes,
despite failing to test things as it was intended. This is also
probably the reason why this bug wasn't reported sooner :)
Thankfully, the test in this case can just as easily be written as
POSIX-compliant as it doesn't use any bash-specific features within the
`[[` block.
h1. Buffers are transient and cannot be relied upon for monitoring
Finally, after fixing the above issue, we started seeing the fluentd
containers being restarted very often, and found an issue with the
underlying logic of the liveness probe.
The probe checks that the pod is still alive by running the following
command:
`find /var/log/fluentd-buffers -type f -newer /tmp/marker-stuck -print -quit`
This checks if any _regular_ file exists under `/var/log/fluentd-buffers`
that is more recent than a predetermined time, and will return an empty
string otherwise.
The issue is that these buffers are temporary and volatile, they get created and
deleted constantly. Here is an example of running that check every second on a
running fluentd:
```
root@fluentd-eks-playground-jdc8m:/# LIVENESS_THRESHOLD_SECONDS=${LIVENESS_THRESHOLD_SECONDS:-300};
root@fluentd-eks-playground-jdc8m:/# STUCK_THRESHOLD_SECONDS=${LIVENESS_THRESHOLD_SECONDS:-900};
root@fluentd-eks-playground-jdc8m:/# touch -d "${STUCK_THRESHOLD_SECONDS} seconds ago" /tmp/marker-stuck;
root@fluentd-eks-playground-jdc8m:/# touch -d "${LIVENESS_THRESHOLD_SECONDS} seconds ago" /tmp/marker-liveness;
root@fluentd-eks-playground-jdc8m:/# while true; do date ; find /var/log/fluentd-buffers -type f -newer /tmp/marker-stuck -print -quit ; sleep 1 ; done
Fri Feb 22 10:52:57 UTC 2019
Fri Feb 22 10:52:58 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer/buffer.b5827964ccf4c7004103c3fa7c8533f85.log
Fri Feb 22 10:52:59 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer/buffer.b5827964ccf4c7004103c3fa7c8533f85.log
Fri Feb 22 10:53:00 UTC 2019
Fri Feb 22 10:53:01 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer/buffer.b5827964fb8b2eedcccd2763ea7775cc2.log
Fri Feb 22 10:53:02 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer/buffer.b5827964fb8b2eedcccd2763ea7775cc2.log
Fri Feb 22 10:53:03 UTC 2019
Fri Feb 22 10:53:04 UTC 2019
Fri Feb 22 10:53:05 UTC 2019
Fri Feb 22 10:53:06 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer/buffer.b5827965564883997b673d703af54848b.log
Fri Feb 22 10:53:07 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer/buffer.b5827965564883997b673d703af54848b.log
Fri Feb 22 10:53:08 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer/buffer.b5827965564883997b673d703af54848b.log
Fri Feb 22 10:53:09 UTC 2019
Fri Feb 22 10:53:10 UTC 2019
Fri Feb 22 10:53:11 UTC 2019
Fri Feb 22 10:53:12 UTC 2019
Fri Feb 22 10:53:13 UTC 2019
Fri Feb 22 10:53:14 UTC 2019
Fri Feb 22 10:53:15 UTC 2019
Fri Feb 22 10:53:16 UTC 2019
```
We can see buffers being created, then disappearing. The LivenessProbe running
under these conditions has a ~50% chance of failing, despite fluentd being
perfectly happy.
I believe that check is probably ok for fluentd installs using large
amounts of buffers, in which case the liveness probe will be correct more
often than not, but fluentd installs that use buffering less intensively
will be negatively impacted by this.
My solution to fix this is to check the last updated time of buffering
_folders_ within `/var/log/fluentd_buffers`. These _do_ get updated when
buffers are created, and do not get deleted as buffers are emptied,
making them the perfect candidate for our use.
Here's an example with the `-d` flag for directories:
```
root@fluentd-eks-playground-jdc8m:/# while true; do date ; find /var/log/fluentd-buffers -type d -newer /tmp/marker-stuck -print -quit ; sleep 1 ; done
Fri Feb 22 10:57:51 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:52 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:53 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:54 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:55 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:56 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:57 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:58 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:57:59 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:58:00 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:58:01 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:58:02 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
Fri Feb 22 10:58:03 UTC 2019
/var/log/fluentd-buffers/kubernetes.system.buffer
```
And example of the directory being updated as new buffers come in:
```
root@fluentd-eks-playground-jdc8m:/# ls -lah /var/log/fluentd-buffers/kubernetes.system.buffer
total 0
drwxr-xr-x 2 root root 6 Feb 22 11:17 .
drwxr-xr-x 3 root root 38 Feb 22 11:14 ..
root@fluentd-eks-playground-jdc8m:/# ls -lah /var/log/fluentd-buffers/kubernetes.system.buffer
total 16K
drwxr-xr-x 2 root root 224 Feb 22 11:18 .
drwxr-xr-x 3 root root 38 Feb 22 11:14 ..
-rw-r--r-- 1 root root 1.8K Feb 22 11:18 buffer.b58279be6e21e8b29fc333a7d50096ed0.log
-rw-r--r-- 1 root root 215 Feb 22 11:18 buffer.b58279be6e21e8b29fc333a7d50096ed0.log.meta
-rw-r--r-- 1 root root 429 Feb 22 11:18 buffer.b58279be6f09bdfe047a96486a525ece2.log
-rw-r--r-- 1 root root 195 Feb 22 11:18 buffer.b58279be6f09bdfe047a96486a525ece2.log.meta
root@fluentd-eks-playground-jdc8m:/# ls -lah /var/log/fluentd-buffers/kubernetes.system.buffer
total 0
drwxr-xr-x 2 root root 6 Feb 22 11:18 .
drwxr-xr-x 3 root root 38 Feb 22 11:14 ..
```
These DaemonSets supports only Linux today, so this change updates the
specs to reflect this limitation. The labels have recently been promoted
to GA. Using the beta labels for now until node-master version skew
problem no longer exists.
setting CPU_LIMITS to '1' fixes the following log appearing every 60 seconds:
Running: kubectl set resources -n kube-system ds fluentd-gcp-v3.1.0 -c fluentd-gcp --requests=cpu=100m,memory=200Mi --limits=cpu=1000m,memory=500Mi
error: info: {extensions v1beta1 daemonsets} "fluentd-gcp-v3.1.0" was not changed
this PR does not change scaler's behaviour, pods are scaled correctly despite error in the logs
Automatic merge from submit-queue (batch tested with PRs 67691, 68147). If you want to cherry-pick this change to another branch, please follow the instructions here: https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md.
Bump versions of components with latest security patches.
**What this PR does / why we need it**:
Upgrade versions of monitoring components used on GCP, to include latest security patches.
**Release note**:
```release-note
[fluentd-gcp-scaler addon] Bump fluentd-gcp-scaler to 0.4 to pick up security fixes.
[prometheus-to-sd addon] Bump prometheus-to-sd to 0.3.1 to pick up security fixes, bug fixes and new features.
[event-exporter addon] Bump event-exporter to 0.2.3 to pick up security fixes.
```
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions here: https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md.
cluster/addons: add labels to fluentd owner files
**What this PR does / why we need it**:
this PR adds SIG labels to fluentd OWNER files:
- cluster/addons/fluentd-elasticsearch/OWNERS
- cluster/addons/fluentd-gcp/OWNERS
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
let me know if the labels need adjustment.
**Release note**:
```release-note
NONE
```
/assign @roberthbailey @mikedanese
/cc @timothysc
/sig gcp
/sig instrumentation
/kind cleanup
