2 min read
When downloading and installing software downloaded from internet on macOS, you might encounter a frustrating "Killed: 9
" error immediately after trying to run the binary. This issue is caused by macOS Gatekeeper security feature that quarantines downloaded files to protect against potentially malicious software.
In this case we are downloading the openshift-client from RedHat, but we won't be able to run it:
$ tar xzvf openshift-client-mac-arm64.tar.gz
x README.md
x oc
x kubectl
$ mv oc ../local/bin/
$ oc
Killed: 9
21/07/2025
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Openshift provides an object that tracks the number of requests made to the Kubernetes API server. It provides insights into the load on the cluster, the performance of applications, and helps in capacity planning. By monitoring APIRequestCount, you can identify potential bottlenecks, detect unusual spikes in traffic, and optimize resource allocation.
$ kubectl get apirequestcounts
NAME REMOVEDINRELEASE REQUESTSINCURRENTHOUR REQUESTSINLAST24H
alertmanagerconfigs.v1alpha1.monitoring.coreos.com 6 1706
alertmanagers.v1.monitoring.coreos.com 20 2891
apiservices.v1.apiregistration.k8s.io 994 99521
(...)
11/07/2023
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After trying to set a custom default certificate for the OpenShift routes we might see how it's Pods starts crashing:
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
router-10-rh8vf 1/1 Running 0 32m
router-10-f2dt2 0/1 CrashLoopBackOff 6 7m
router-10-m45b7 1/1 Running 0 31m
Checking it's logs we'll get a quite misleading message:
$ kubectl logs router-10-f2dt2 -n default
Error from server: Get https://some.openshift.cluster:10250/containerLogs/default/router-10-f2dt2/router: x509: certificate has expired or is not yet valid
04/07/2023
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If we want to take a look at the network traffic that we get out of an OpenShift node we can use the oc debug command to spin up a privileged pod with tcpdump installed. This way we don't need to ssh into the worker node.
22/05/2023
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When running an OpenShift cluster we'll find that it exposes a web-based console that not only allows you to deploy applications, but also managing the cluster. However, since it is an additional way to access the cluster we might have some concerns about it, specially from the security perspective. Specifically, the console can be a potential attack vector to gain unauthorized access to the cluster. Let's see how to disable it.
26/01/2023
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