Alpine Linux - User contributions [en]

Postgresql 16

2025-02-18T02:01:01Z

Dvh312: Fix restart command

PostgreSQL is a well known opensource database that scales well and is easy to use. In Alpine v3.20 we can install the latest version using the package postgresql16

== Installation ==
{{Cmd|apk add {{pkg|postgresql16|arch=}} {{pkg|postgresql16-contrib|arch=}} {{pkg|postgresql16-openrc|arch=}}}}
{{Cmd|rc-update add postgresql}}
{{Cmd|rc-service postgresql start}}

This will start the postgresql 16 server and perform some initial configuration.

== Configuration ==

Login as the postgres user and start psql to create a new user and database:
{{Cmd|su postgres}}
{{Cmd|psql}}
{{Cmd|create user user with encrypted password 'password';}}
{{Cmd|create database database;}}
{{Cmd|grant all privileges on database database to user;}}

=== Network access ===

By default only local access is allowed to PostgreSQL. To allow other networked services to access the database we need to configure PostgreSQL to allow external connections.

Edit the {{Path|/etc/postgresql16/postgresql.conf}} file using <code>nano</code> or any other {{ic|<editor> /etc/postgresql16/postgresql.conf}}
Find the line that starts with <pre>#listen_addresses = 'localhost'</pre>
Uncomment it and change it to the following:
<pre>listen_addresses = '*'</pre>
If you want it to listen on a specific ip you can change * to 192.168.1.2/24.
Save the file and change the next config file.

Modify the {{Path|/etc/postgresql16/pg_hba.conf}} file using <code>nano</code> or any other {{ic|<editor> /etc/postgresql16/pg_hba.conf}}
Look for the line: <pre>host all all 127.0.0.1/32 md5</pre>
And change it to: <pre>host all all 0.0.0.0/0 md5</pre>
This line allows connections from any IP address and requires a password for authentication (md5).
Restart the server to allow incoming connections from other hosts. {{Cmd|rc-service postgresql restart}}

Allow the port through the firewall. For [[UFW]] firewall type: {{Cmd|ufw allow 5432}}

This is a basic configuration. You can configure the PostgreSQL server to only allow certain networks or IP's to connect but thats beyond the scope of this documentation.

== Upgrading PostgreSQL ==

{{Todo| Need to add Notes on upgrading PostgreSQL }}

== Troubleshooting ==

{{Todo|Need to add troubleshooting examples}}

== See also ==
* https://blog.devart.com/configure-postgresql-to-allow-remote-connection.html

[[Category:Database]]

[[Category:Server]]

K8s

2023-04-05T05:45:37Z

Dvh312: Enable ip_forward

= Alpine Linux 🌲 K8s in 10 Minutes =

== Summary ==

This guide will allow you to deploy a fresh Alpine Linux install into a Kubernetes K8 cluster in less than 10 minutes.

== Why ✨ ==

I went to learn Kubernetes recently and I built a k3 cluster using Alpine in an hour or so, it was a great experience. I figured the next step would be K8s, but I found no material on K8s for Alpine. This guide is the result of my first pass and the incorporations of high quality notes from the contributers. Kubernetes 🦄 is awesome.

== Contributers ==

* Matthew Rogers [https://github.com/RamboRogers Github] [https://www.linkedin.com/in/matthewrogerscissp/ LinkedIn]
* Mike Zolla [https://github.com/Zolla-Zolla Github] [https://www.linkedin.com/in/mike-zolla-5903b8/ LinkedIn]
* Matthew Emmett [https://github.com/mattemmett Github] [https://www.linkedin.com/in/mattemmett/ LinkedIn]

-----

= Build K8s on Alpine Linux 🌲 =

=== Prerequisits 🔍 ===

You need an [https://alpinelinux.org/ Alpine Linux] install (this guide is written against version 3.17 standard image) with internet access. I recommend at least 2 CPU with 4GB of ram and 10GB of disk for each node.

<blockquote>For HA control planes you'll need a mininum of three nodes
</blockquote>
=== 1. Setup the Repositories 📗 ===

Update you repositories under /etc/apk/repositories to include community, edge community and testing.

<pre>#/media/cdrom/apks
http://dl-cdn.alpinelinux.org/alpine/v3.17/main
http://dl-cdn.alpinelinux.org/alpine/v3.17/community
#http://dl-cdn.alpinelinux.org/alpine/edge/main
http://dl-cdn.alpinelinux.org/alpine/edge/community
http://dl-cdn.alpinelinux.org/alpine/edge/testing
</pre>
=== 2. Node Setup 🖥️ ===

This series of commands solves a series is incremental problems and sets up the system (if the first control node) for kubectl/kubeadm to run properly on next login by linking the config.

The result here gives you a functional node that can be joined to an existing cluster or can become the first control plane of a new cluster. 🎶

<blockquote>*** 🔔 This build assumes CNI usage of flannel for networking 🔔 ***
</blockquote>
<pre>#add kernel module for networking stuff
echo "br_netfilter" > /etc/modules-load.d/k8s.conf
modprobe br_netfilter
echo 1 > /proc/sys/net/ipv4/ip_forward
apk add cni-plugin-flannel
apk add cni-plugins
apk add flannel
apk add flannel-contrib-cni
apk add kubelet
apk add kubeadm
apk add kubectl
apk add containerd
apk add uuidgen
apk add nfs-utils
#get rid of swap
cat /etc/fstab | grep -v swap > temp.fstab
cat temp.fstab > /etc/fstab
rm temp.fstab
swapoff -a
#Fix prometheus errors
mount --make-rshared /
echo "#!/bin/sh" > /etc/local.d/sharemetrics.start
echo "mount --make-rshared /" >> /etc/local.d/sharemetrics.start
chmod +x /etc/local.d/sharemetrics.start
rc-update add local
#Fix id error messages
uuidgen > /etc/machine-id
#Add services
rc-update add containerd
rc-update add kubelet
#Sync time
rc-update add ntpd
/etc/init.d/ntpd start
/etc/init.d/containerd start
#fix flannel
ln -s /usr/libexec/cni/flannel-amd64 /usr/libexec/cni/flannel
#kernel stuff
echo "net.bridge.bridge-nf-call-iptables=1" >> /etc/sysctl.conf
sysctl net.bridge.bridge-nf-call-iptables=1
#Pin your versions! If you update and the nodes get out of sync, it implodes.
apk add 'kubelet=~1.26'
apk add 'kubeadm=~1.26'
apk add 'kubectl=~1.26'
#Note that in the future you will manually have to add a newer version the same way to upgrade.
</pre>
Your blank node is now ready! If it's the first, you'll want to make a control node.

=== 3. Setup the Control Plane (New Cluster!) 🦾 ===

Run this command to start the cluster and then apply a network.

<pre>
#do not change subnet
kubeadm init --pod-network-cidr=10.244.0.0/16 --node-name=$(hostname)
mkdir ~/.kube
ln -s /etc/kubernetes/admin.conf /root/.kube/config
kubectl apply -f https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml
</pre>
You now have a control plane. This also gives you the command to run on our blank nodes to add them to this cluster as workers.

=== 4. Join the cluster. 🐜 ===

Run this to get the join command from the control plane which you would then run on your new worker.
<pre>
kubeadm token create --print-join-command
</pre>

= Bonus 💰 =

== Setup NFS Mounts on K8s ==

This can be shared NFS storage to allow for auto persistent claim fulfilment. You'll need your IP updated and export information.

<pre>helm repo add nfs-subdir-external-provisioner https://kubernetes-sigs.github.io/nfs-subdir-external-provisioner/
helm install nfs-subdir-external-provisioner nfs-subdir-external-provisioner/nfs-subdir-external-provisioner \
--set nfs.server=192.168.1.31 \
--set nfs.path=/exports/cluster00
</pre>
Now set the default storage class for the cluster.

<pre>kubectl get storageclass
kubectl patch storageclass nfs-client -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'
</pre>
== Check on System 👀 ==

Check on your system.

<pre>kubectl get nodes
kubectl get all
</pre>

K8s

2023-04-05T05:18:38Z

Dvh312: Update to Alpine 3.17

= Alpine Linux 🌲 K8s in 10 Minutes =

== Summary ==

This guide will allow you to deploy a fresh Alpine Linux install into a Kubernetes K8 cluster in less than 10 minutes.

== Why ✨ ==

I went to learn Kubernetes recently and I built a k3 cluster using Alpine in an hour or so, it was a great experience. I figured the next step would be K8s, but I found no material on K8s for Alpine. This guide is the result of my first pass and the incorporations of high quality notes from the contributers. Kubernetes 🦄 is awesome.

== Contributers ==

* Matthew Rogers [https://github.com/RamboRogers Github] [https://www.linkedin.com/in/matthewrogerscissp/ LinkedIn]
* Mike Zolla [https://github.com/Zolla-Zolla Github] [https://www.linkedin.com/in/mike-zolla-5903b8/ LinkedIn]
* Matthew Emmett [https://github.com/mattemmett Github] [https://www.linkedin.com/in/mattemmett/ LinkedIn]

-----

= Build K8s on Alpine Linux 🌲 =

=== Prerequisits 🔍 ===

You need an [https://alpinelinux.org/ Alpine Linux] install (this guide is written against version 3.17 standard image) with internet access. I recommend at least 2 CPU with 4GB of ram and 10GB of disk for each node.

<blockquote>For HA control planes you'll need a mininum of three nodes
</blockquote>
=== 1. Setup the Repositories 📗 ===

Update you repositories under /etc/apk/repositories to include community, edge community and testing.

<pre>#/media/cdrom/apks
http://dl-cdn.alpinelinux.org/alpine/v3.17/main
http://dl-cdn.alpinelinux.org/alpine/v3.17/community
#http://dl-cdn.alpinelinux.org/alpine/edge/main
http://dl-cdn.alpinelinux.org/alpine/edge/community
http://dl-cdn.alpinelinux.org/alpine/edge/testing
</pre>
=== 2. Node Setup 🖥️ ===

This series of commands solves a series is incremental problems and sets up the system (if the first control node) for kubectl/kubeadm to run properly on next login by linking the config.

The result here gives you a functional node that can be joined to an existing cluster or can become the first control plane of a new cluster. 🎶

<blockquote>*** 🔔 This build assumes CNI usage of flannel for networking 🔔 ***
</blockquote>
<pre>#add kernel module for networking stuff
echo "br_netfilter" > /etc/modules-load.d/k8s.conf
modprobe br_netfilter
apk add cni-plugin-flannel
apk add cni-plugins
apk add flannel
apk add flannel-contrib-cni
apk add kubelet
apk add kubeadm
apk add kubectl
apk add containerd
apk add uuidgen
apk add nfs-utils
#get rid of swap
cat /etc/fstab | grep -v swap > temp.fstab
cat temp.fstab > /etc/fstab
rm temp.fstab
swapoff -a
#Fix prometheus errors
mount --make-rshared /
echo "#!/bin/sh" > /etc/local.d/sharemetrics.start
echo "mount --make-rshared /" >> /etc/local.d/sharemetrics.start
chmod +x /etc/local.d/sharemetrics.start
rc-update add local
#Fix id error messages
uuidgen > /etc/machine-id
#Add services
rc-update add containerd
rc-update add kubelet
#Sync time
rc-update add ntpd
/etc/init.d/ntpd start
/etc/init.d/containerd start
#fix flannel
ln -s /usr/libexec/cni/flannel-amd64 /usr/libexec/cni/flannel
#kernel stuff
echo "net.bridge.bridge-nf-call-iptables=1" >> /etc/sysctl.conf
sysctl net.bridge.bridge-nf-call-iptables=1
#Pin your versions! If you update and the nodes get out of sync, it implodes.
apk add 'kubelet=~1.26'
apk add 'kubeadm=~1.26'
apk add 'kubectl=~1.26'
#Note that in the future you will manually have to add a newer version the same way to upgrade.
</pre>
Your blank node is now ready! If it's the first, you'll want to make a control node.

=== 3. Setup the Control Plane (New Cluster!) 🦾 ===

Run this command to start the cluster and then apply a network.

<pre>
#do not change subnet
kubeadm init --pod-network-cidr=10.244.0.0/16 --node-name=$(hostname)
mkdir ~/.kube
ln -s /etc/kubernetes/admin.conf /root/.kube/config
kubectl apply -f https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml
</pre>
You now have a control plane. This also gives you the command to run on our blank nodes to add them to this cluster as workers.

=== 4. Join the cluster. 🐜 ===

Run this to get the join command from the control plane which you would then run on your new worker.
<pre>
kubeadm token create --print-join-command
</pre>

= Bonus 💰 =

== Setup NFS Mounts on K8s ==

This can be shared NFS storage to allow for auto persistent claim fulfilment. You'll need your IP updated and export information.

<pre>helm repo add nfs-subdir-external-provisioner https://kubernetes-sigs.github.io/nfs-subdir-external-provisioner/
helm install nfs-subdir-external-provisioner nfs-subdir-external-provisioner/nfs-subdir-external-provisioner \
--set nfs.server=192.168.1.31 \
--set nfs.path=/exports/cluster00
</pre>
Now set the default storage class for the cluster.

<pre>kubectl get storageclass
kubectl patch storageclass nfs-client -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'
</pre>
== Check on System 👀 ==

Check on your system.

<pre>kubectl get nodes
kubectl get all
</pre>

K8s

2023-04-05T05:09:24Z

Dvh312: Upgrade to kube 1.26, use containerd instead, set node-name to hostname to avoid not found on network

= Alpine Linux 🌲 K8s in 10 Minutes =

== Summary ==

This guide will allow you to deploy a fresh Alpine Linux install into a Kubernetes K8 cluster in less than 10 minutes.

== Why ✨ ==

I went to learn Kubernetes recently and I built a k3 cluster using Alpine in an hour or so, it was a great experience. I figured the next step would be K8s, but I found no material on K8s for Alpine. This guide is the result of my first pass and the incorporations of high quality notes from the contributers. Kubernetes 🦄 is awesome.

== Contributers ==

* Matthew Rogers [https://github.com/RamboRogers Github] [https://www.linkedin.com/in/matthewrogerscissp/ LinkedIn]
* Mike Zolla [https://github.com/Zolla-Zolla Github] [https://www.linkedin.com/in/mike-zolla-5903b8/ LinkedIn]
* Matthew Emmett [https://github.com/mattemmett Github] [https://www.linkedin.com/in/mattemmett/ LinkedIn]

-----

= Build K8s on Alpine Linux 🌲 =

=== Prerequisits 🔍 ===

You need an [https://alpinelinux.org/ Alpine Linux] install (this guide is written against version 3.15 standard image) with internet access. I recommend at least 2 CPU with 4GB of ram and 10GB of disk for each node.

<blockquote>For HA control planes you'll need a mininum of three nodes
</blockquote>
=== 1. Setup the Repositories 📗 ===

Update you repositories under /etc/apk/repositories to include community, edge community and testing.

<pre>#/media/cdrom/apks
http://dl-cdn.alpinelinux.org/alpine/v3.15/main
http://dl-cdn.alpinelinux.org/alpine/v3.15/community
#http://dl-cdn.alpinelinux.org/alpine/edge/main
http://dl-cdn.alpinelinux.org/alpine/edge/community
http://dl-cdn.alpinelinux.org/alpine/edge/testing
</pre>
=== 2. Node Setup 🖥️ ===

This series of commands solves a series is incremental problems and sets up the system (if the first control node) for kubectl/kubeadm to run properly on next login by linking the config.

The result here gives you a functional node that can be joined to an existing cluster or can become the first control plane of a new cluster. 🎶

<blockquote>*** 🔔 This build assumes CNI usage of flannel for networking 🔔 ***
</blockquote>
<pre>#add kernel module for networking stuff
echo "br_netfilter" > /etc/modules-load.d/k8s.conf
modprobe br_netfilter
apk add cni-plugin-flannel
apk add cni-plugins
apk add flannel
apk add flannel-contrib-cni
apk add kubelet
apk add kubeadm
apk add kubectl
apk add containerd
apk add uuidgen
apk add nfs-utils
#get rid of swap
cat /etc/fstab | grep -v swap > temp.fstab
cat temp.fstab > /etc/fstab
rm temp.fstab
swapoff -a
#Fix prometheus errors
mount --make-rshared /
echo "#!/bin/sh" > /etc/local.d/sharemetrics.start
echo "mount --make-rshared /" >> /etc/local.d/sharemetrics.start
chmod +x /etc/local.d/sharemetrics.start
rc-update add local
#Fix id error messages
uuidgen > /etc/machine-id
#Add services
rc-update add containerd
rc-update add kubelet
#Sync time
rc-update add ntpd
/etc/init.d/ntpd start
/etc/init.d/containerd start
#fix flannel
ln -s /usr/libexec/cni/flannel-amd64 /usr/libexec/cni/flannel
#kernel stuff
echo "net.bridge.bridge-nf-call-iptables=1" >> /etc/sysctl.conf
sysctl net.bridge.bridge-nf-call-iptables=1
#Pin your versions! If you update and the nodes get out of sync, it implodes.
apk add 'kubelet=~1.26'
apk add 'kubeadm=~1.26'
apk add 'kubectl=~1.26'
#Note that in the future you will manually have to add a newer version the same way to upgrade.
</pre>
Your blank node is now ready! If it's the first, you'll want to make a control node.

=== 3. Setup the Control Plane (New Cluster!) 🦾 ===

Run this command to start the cluster and then apply a network.

<pre>
#do not change subnet
kubeadm init --pod-network-cidr=10.244.0.0/16 --node-name=$(hostname)
mkdir ~/.kube
ln -s /etc/kubernetes/admin.conf /root/.kube/config
kubectl apply -f https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml
</pre>
You now have a control plane. This also gives you the command to run on our blank nodes to add them to this cluster as workers.

=== 4. Join the cluster. 🐜 ===

Run this to get the join command from the control plane which you would then run on your new worker.
<pre>
kubeadm token create --print-join-command
</pre>

= Bonus 💰 =

== Setup NFS Mounts on K8s ==

This can be shared NFS storage to allow for auto persistent claim fulfilment. You'll need your IP updated and export information.

<pre>helm repo add nfs-subdir-external-provisioner https://kubernetes-sigs.github.io/nfs-subdir-external-provisioner/
helm install nfs-subdir-external-provisioner nfs-subdir-external-provisioner/nfs-subdir-external-provisioner \
--set nfs.server=192.168.1.31 \
--set nfs.path=/exports/cluster00
</pre>
Now set the default storage class for the cluster.

<pre>kubectl get storageclass
kubectl patch storageclass nfs-client -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'
</pre>
== Check on System 👀 ==

Check on your system.

<pre>kubectl get nodes
kubectl get all
</pre>