This document describes how to setup the MicroShift development environment running in a virtual machine.
Start by downloading one of the DVD ISO images for the x86_64
or aarch64
architecture:
- RHEL 9.4 from https://developers.redhat.com/products/rhel/download
- CentOS 9 Stream from https://www.centos.org/download
Log into the hypervisor host and run the following commands to create a RHEL virtual machine with 4 cores, 8GB of RAM and 100GB of storage.
See Increase Virtual Machine Disk Size section for increasing the storage size if necessary.
Move the DVD ISO image to /var/lib/libvirt/images
directory and run the following
commands to install the libvirt
packages and create a virtual machine.
VMNAME="microshift-dev"
git clone https://github.com/openshift/microshift.git ~/microshift
cd ~/microshift
./scripts/devenv-builder/manage-vm.sh config
./scripts/devenv-builder/manage-vm.sh create -n ${VMNAME}
Note that the manage-vm.sh
script can also be used on the hypervisor host to
manipulate the virtual machines where MicroShift will run.
- Use the
create
subcommand to create a new virtual machine - Use the
delete
subcommand to remove a virtual machine - Use the
ip
subcommand to find the IP address of a virtual machine
If your host is configured with virtual machine disk storage somewhere other than the
default, set MICROSHIFT_VMDISKDIR
to point to the location (e.g. "${HOME}/VMs").
Set MICROSHIFT_SSH_KEY_FILE
to the path to an SSH public key to have that key
added to the virtual machine for easier login.
After the virtual machine installation is finished, the manage-vm.sh
script
prompts for a user name and password to register the operating system with a
Red Hat subscription.
A valid Red Hat subscription is required before running the virtual machine configuration procedure.
Proceed by downloading the OpenShift pull secret from the
https://console.redhat.com/openshift/downloads#tool-pull-secret page and store
it in the ~/.pull-secret.json
file.
The pull secret will also be used in the CRI-O
configuration for pulling the
MicroShift container images.
Run the following command to configure SSH, SUDO, upgrade the system, firewall, build and install MicroShift including its runtime dependencies, Kubernetes client utilities, and enable remote Cockpit console.
VMIPADDR=$(./scripts/devenv-builder/manage-vm.sh ip -n ${VMNAME})
# Enter 'microshift' without quotes as a password if prompted
ssh-copy-id -f microshift@${VMIPADDR}
scp ./scripts/devenv-builder/configure-vm.sh microshift@${VMIPADDR}:
scp ~/.pull-secret.json microshift@${VMIPADDR}:
ssh -t microshift@${VMIPADDR} "~/configure-vm.sh ~/.pull-secret.json"
The script prompts for Red Hat subscription credentials if the system has not been registered yet.
The configuration script should run unattended and finish with the following message.
The configuration phase completed. Run the following commands to:
- Wait until all MicroShift pods are running
watch sudo $(which oc) --kubeconfig /var/lib/microshift/resources/kubeadmin/kubeconfig get pods -A
- Get MicroShift logs
sudo journalctl -u microshift
- Get microshift-etcd logs
sudo journalctl -u microshift-etcd.scope
- Clean up MicroShift service configuration
echo 1 | sudo /usr/bin/microshift-cleanup-data --all
Done
You should now be able to access the virtual machine Cockpit console using the
https://${VMIPADDR}:9090
URL.
Log into the development virtual machine with the microshift:microshift
user
credentials.
The https://github.com/openshift/microshift.git
MicroShift repository is already
available at ~/microshift
directory as an artifact of the configure-vm.sh
script executed in the previous steps.
Run make
command in the top-level directory. If necessary, add DEBUG=true
argument to the make
command for building a binary with debug symbols.
cd ~/microshift
make clean
make
The artifact of the build is the microshift
executable file located in the
_output/bin
directory.
Run make command with the rpm
or srpm
argument in the top-level directory.
cd ~/microshift
make rpm
make srpm
The artifacts of the build are located in the _output/rpmbuild
directory.
Stop the MicroShift service and clean up its configuration data before running a standalone MicroShift executable.
echo 1 | sudo ~/microshift/scripts/microshift-cleanup-data.sh --all --keep-images
Run the MicroShift executable file in the background using the following command.
nohup sudo ~/microshift/_output/bin/microshift run >> ~/microshift.log &
Examine the ~/microshift.log
log file to ensure a successful startup.
An alternative way of running MicroShift is to update
/usr/bin/microshift
file and restart the service. The logs would then be accessible by running thejournalctl -xu microshift
command.sudo cp -f ~/microshift/_output/bin/microshift /usr/bin/microshift sudo systemctl restart microshift
Copy kubeconfig
to the default location that can be accessed without the
administrator privilege.
mkdir -p ~/.kube/
sudo cat /var/lib/microshift/resources/kubeadmin/kubeconfig > ~/.kube/config
Verify that the MicroShift is up and running.
oc get cs
watch oc get pods -A
Run the following commands to stop the MicroShift process and make sure it is shut down by examining its log file.
sudo kill microshift && sleep 3
tail -3 ~/microshift.log
If MicroShift is running as a service, it is necessary to execute the
sudo systemctl stop microshift
command to shut it down and review the output of thejournalctl -xu microshift
command to verify the service termination.
This command only stops the MicroShift process. To perform the full cleanup including
CRI-O
, MicroShift and OVN caches, run the following script.
echo 1 | sudo ~/microshift/scripts/microshift-cleanup-data.sh --all
The full cleanup does not remove OVS configuration applied by the MicroShift service initialization sequence. Run the
sudo /usr/bin/configure-ovs.sh OpenShiftSDN
command to revert to the original network settings.
During the development cycle, it is practical to build and run MicroShift executable as demonstrated in the Building MicroShift and Running MicroShift sections above. However, it is also necessary to have a convenient technique for testing the system in a setup resembling the production environment. Such an environment can be created in a virtual machine as described in the Install MicroShift on RHEL for Edge document.
Once a RHEL for Edge virtual machine is created, it is running a version of MicroShift with the latest changes. When MicroShift code is updated and the executable file is rebuilt with the new changes, the updates need to be installed on RHEL for Edge OS.
Since it takes a long time to create a new RHEL for Edge installer ISO and deploy it on a virtual machine, the remainder of this section describes a simple technique for replacing the MicroShift executable file on an existing RHEL for Edge OS installation.
Log into the RHEL for Edge machine using redhat:redhat
credentials. Run the following
command for configuring the ostree to allow transient overlays on top of the /usr directory.
sudo rpm-ostree usroverlay
This would enable a development mode where users can overwrite /usr
directory contents.
Note that all changes will be discarded on reboot.
Log into the development virtual machine with the microshift:microshift
user credentials.
It is recommended to update the local /etc/hosts
to resolve the microshift-edge
host name or use its IP address as presented below. Also, copy the local SSH keys
to allow the microshift
user to run SSH commands without a password on the RHEL
for Edge machine.
VMIPADDR=192.168.122.101
ssh-copy-id redhat@${VMIPADDR}
Rebuild the MicroShift executable as described in the Building MicroShift Executable section and run the following commands to copy, cleanup, replace and restart the new service on the RHEL for Edge system.
scp ~/microshift/_output/bin/{microshift,microshift-etcd} redhat@${VMIPADDR}:
ssh redhat@${VMIPADDR} ' \
echo 1 | sudo /usr/bin/microshift-cleanup-data --all --keep-images && \
sudo cp -f ~redhat/{microshift,microshift-etcd} /usr/bin/ && \
sudo systemctl enable microshift --now && \
echo Done '
Golang pprof is a useful tool for serving
runtime profiling data via an HTTP server in the format expected by the pprof
visualization tool.
Runtime profiling data can be accessed from the command line as described in the pprof documentation. As an example, the following command can be used to look at the heap profile.
oc get --raw /debug/pprof/heap > heap.pprof
go tool pprof heap.pprof
To view all the available profiles, run oc get --raw /debug/pprof
.
The following error message may be encountered when enabling the OpenShift RPM repositories.
Error: 'fast-datapath-for-rhel-9-x86_64-rpms' does not match a valid repository ID.
Use "subscription-manager repos --list" to see valid repositories.
To mitigate this problem, make sure that your system is registered and attached
to the Red Hat Openshift Container Platform
or equivalent subscription. Once the
proper subscription is configured, run the subscription-manager
command to verify
the enabled repositories.
$ sudo subscription-manager repos --list-enabled
+----------------------------------------------------------+
Available Repositories in /etc/yum.repos.d/redhat.repo
+----------------------------------------------------------+
Repo ID: rhel-9-for-x86_64-baseos-rpms
Repo Name: Red Hat Enterprise Linux 9 for x86_64 - BaseOS (RPMs)
Repo URL: https://cdn.redhat.com/content/dist/rhel9/$releasever/x86_64/baseos/os
Enabled: 1
Repo ID: fast-datapath-for-rhel-9-x86_64-rpms
Repo Name: Fast Datapath for RHEL 9 x86_64 (RPMs)
Repo URL: https://cdn.redhat.com/content/dist/layered/rhel9/x86_64/fast-datapath/os
Enabled: 1
Repo ID: rhel-9-for-x86_64-appstream-rpms
Repo Name: Red Hat Enterprise Linux 9 for x86_64 - AppStream (RPMs)
Repo URL: https://cdn.redhat.com/content/dist/rhel9/$releasever/x86_64/appstream/os
Enabled: 1
Log into the hypervisor host, and run the following commands to resize its disk.
VM_NAME=microshift-dev
VM_DISK=/var/lib/libvirt/images/${VM_NAME}.qcow2
INCREASE_BY=20
sudo virsh shutdown ${VM_NAME}
# Wait until the host is shut off
sudo qemu-img resize ${VM_DISK} +${INCREASE_BY}G
sudo virsh start ${VM_NAME}
Log into the virtual machine and run the following commands to extend its root partition.
# Use 'lsblk' command output to see your device and partition to be resized
DEVICE=/dev/vda
PARTNUM=3
# Resize the device
sudo parted ${DEVICE} ---pretend-input-tty resizepart ${PARTNUM} 100%
sudo pvresize ${DEVICE}${PARTNUM}
sudo lvextend -l +95%FREE /dev/mapper/rhel-root
# Resize the file system
sudo xfs_growfs /dev/mapper/rhel-root