91eb94baaa
The IPAM pool analyzer checks that utilization of the pod IP subnet is
less than 85%. For example, if using 10.32.0.0/12, this analyzer will
warn if 3,482 IPs are currently allocated to pods.
The pending allocation analyzer checks that the IPAM status in the
report has no items for the PendingAllocates field. This indicates the
IPAM service is not ready according to the code in the weave status
template
e3712152d2/prog/weaver/http.go (L186).
The weave connections analyzer checks that all connections to remote
peers are in the established state. The state will be "pending" if UDP
is blocked between nodes and will be "failed" if the weave pod on the
remote node is in a crash loop. To force a pending state for testing,
run the commands `iptables -A INPUT -p udp --dport 6784 -j REJECT` and
`iptables -A INPUT -p udp --dport 6783 -j REJECT` on a peer.
The weave connections analyzer also checks that all connections are
using the fastdp protocol. A commopn issue seen in the field on
CentOS/RHEL 7 is that some sides of a connection are using fastdp and
other sides have fallen back to sleeve. Set the WEAVE_NO_FASTDP env var
on the weave daemonset to "true" to test this analyzer.
Replicated Troubleshoot
Replicated Troubleshoot is a framework for collecting, redacting, and analyzing highly customizable diagnostic information about a Kubernetes cluster. Troubleshoot specs are created by 3rd-party application developers/maintainers and run by cluster operators in the initial and ongoing operation of those applications.
Troubleshoot provides two CLI tools as kubectl plugins (using Krew): kubectl preflight and kubectl support-bundle. Preflight provides pre-installation cluster conformance testing and validation (preflight checks) and support-bundle provides post-installation troubleshooting and diagnostics (support bundles).
Preflight Checks
Preflight checks are an easy-to-run set of conformance tests that can be written to verify that specific requirements in a cluster are met.
To run a sample preflight check from a sample application, install the preflight kubectl plugin:
curl https://krew.sh/preflight | bash
and run:
kubectl preflight https://preflight.replicated.com
For a details on creating the custom resource files that drive preflight checks, visit creating preflight checks.
Support Bundle
A support bundle is an archive that's created in-cluster, by collecting logs and cluster information, and executing specified commands (including redaction of sensitive information). After creating a support bundle, the cluster operator will normally deliver it to the 3rd-party application vendor for analysis and disconnected debugging. Another Replicated project, KOTS, provides k8s apps an in-cluster UI for processing support bundles and viewing analyzers (as well as support bundle collection).
To collect a sample support bundle, install the troubleshoot kubectl plugin:
curl https://krew.sh/support-bundle | bash
and run:
kubectl support-bundle https://support-bundle.replicated.com
For details on creating the custom resource files that drive support-bundle collection, visit creating collectors and creating analyzers.
Community
For questions about using Troubleshoot, there's a Replicated Community forum, and a #app-troubleshoot channel in Kubernetes Slack.