Deployment Troubleshooting

Local deployment with MicroK8s - suggestions:

  • use v1.15 of MicroK8s (higher version not yet supported) (details in "Installation of mojaloop helm charts fail with validation failed" section)
  • try microk8s.inspect for hints (for example connectivity problems when ip forwarding is not enabled, more about it in "MicroK8s - Connectivity Issues section")
  • enable following microk8s add-ons (check with sudo microk8s.status):
    • storage
    • ingress
    • dns
    • istio
    • dashboard

1. Known issues

1.1. Mojaloop Helm Charts does not support Kubernetes v1.16 or greater

Description

When installing mojaloop helm charts, the following error occurs:

   Error: validation failed: [unable to recognize "": no matches for kind "Deployment" in version "apps/v1beta2", unable to recognize "": no matches for kind "Deployment" in version "extensions/v1beta1", unable to recognize "": no matches for kind "StatefulSet" in version "apps/v1beta2", unable to recognize "": no matches for kind "StatefulSet" in version "apps/v1beta1"]

Reason

In version 1.16 of Kubernetes breaking change has been introduced (more about it in "Deprecations and Removals" of Kubernetes release notes. The Kubernetes API versions apps/v1beta1 and apps/v1beta2are no longer supported and and have been replaced by apps/v1.

Currently Mojaloop helm charts (as of v8.4.x) refer to deprecated ids, therefore it's not possible to install current Mojaloop charts on Kubernetes version above 1.15 without manually changing charts.

Refer to the following issue for more info: mojaloop/helm#219

Fixes

Ensure that you are deploying the Mojaloop Helm charts on v1.15 of Kubernetes (or microk8s when working locally).

Additional details for microk8s fix

To check version of microk8s:

   snap info microk8s

Note: Look at the end of the output for a row starting with "installed"

To install most recent supported version:

   snap refresh microk8s --channel=1.15/stable --classic

2. Deployment issues

2.1. MicroK8s - helm init connection refused

Description

The helm init:

   helm init

fails with error when installing locally on microk8s:

   Error: error installing: Post http://localhost:8080/apis/apps/v1/namespaces/kube-system/deployments: dial tcp 127.0.0.1:8080: connect: connection refused

Reason

This may be a missing ~/.kube/config file, where helm looks for connection details.

Fix - option #1

One of the solutions is to generate that file by issuing:

   microk8s.kubectl config view --raw > $HOME/.kube/config

Fix - option #2

Another option is to export the config to a new file:

   microk8s.kubectl config view --raw > $HOME/.kube/local.config

And then export the following env var:

   export KUBECONFIG=$HOME/.kube/local.config

2.2. ERR_NAME_NOT_RESOLVED Error

Description

The following error is displayed when attempting to access an end-point (e.g. central-ledger.local) via the Kubernetes Service directly in a browser: ERR_NAME_NOT_RESOLVED

Fixes

  • Verify that that Mojaloop was deployed by checking that the helm chart(s) was installed by executing:

      helm list
    

    If the helm charts are not listed, see the Helm Chart Installation section to install a chart.

  • Ensure that all the Mojaloop Pods/Containers have started up correctly and are available through the Kubernetes dashboard.

  • Note that the Mojaloop deployment via Helm can take a few minutes to initially startup depending on the system's available resources and specification. It is recommended that you wait at least 10m for all Pods/Containers to self heal before troubleshooting.

2.3. MicroK8s - Connectivity Issues

Description

My pods can’t reach the internet or each other (but my MicroK8s host machine can).

An example of this is that the Central-Ledger logs indicate that there is an error with the Broker transport as per the following example:

2019-11-05T12:28:10.470Z - info: Server running at: 
2019-11-05T12:28:10.474Z - info: Handler Setup - Registering {"type":"prepare","enabled":true}!
2019-11-05T12:28:10.476Z - info: CreateHandler::connect - creating Consumer for topics: [topic-transfer-prepare]
2019-11-05T12:28:10.515Z - info: CreateHandler::connect - successfully connected to topics: [topic-transfer-prepare]
2019-11-05T12:30:20.960Z - error: Consumer::onError()[topics='topic-transfer-prepare'] - Error: Local: Broker transport failure)

Fixes

Make sure packets to/from the pod network interface can be forwarded to/from the default interface on the host via the iptables tool. Such changes can be made persistent by installing the iptables-persistent package:

sudo iptables -P FORWARD ACCEPT
sudo apt-get install iptables-persistent

or, if using ufw:

sudo ufw default allow routed

The MicroK8s inspect command can be used to check the firewall configuration:

microk8s.inspect

3. Ingress issues

3.1. Ingress rules are not resolving for Nginx Ingress v0.22 or later

Description

Ingress rules are unable to resolve to the correct path based on the annotations specified in the values.yaml configuration files when using Nginx Ingress controllers v0.22 or later.

This is due to the changes introduced in Nginx Ingress controllers that are v0.22 or later as per the following link: https://kubernetes.github.io/ingress-nginx/examples/rewrite/#rewrite-target.

Fixes

  • Make the following change to all Ingress annotations (from --> to) in each of the values.yaml files:

    nginx.ingress.kubernetes.io/rewrite-target: '/' --> nginx.ingress.kubernetes.io/rewrite-target: '/$1'

3.2. Ingress rules are not resolving for Nginx Ingress earlier than v0.22

Description

Ingress rules are unable to resolve to the correct path based on the annotations specified in the values.yaml configuration files when using Nginx Ingress controllers that are older than v0.22.

This is due to the changes introduced in Nginx Ingress controllers that are v0.22 or later as per the following link: https://kubernetes.github.io/ingress-nginx/examples/rewrite/#rewrite-target.

Fixes

  • Make the following change to all Ingress annotations (from --> to) in each of the values.yaml files:

    nginx.ingress.kubernetes.io/rewrite-target: '/$1' --> nginx.ingress.kubernetes.io/rewrite-target: '/'

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