1
0
mirror of https://github.com/openshift/openshift-docs.git synced 2026-02-05 12:46:18 +01:00
Files
openshift-docs/migrating_from_ocp_3_to_4/migrating-applications-3-4.adoc

63 lines
3.3 KiB
Plaintext

:_mod-docs-content-type: ASSEMBLY
[id="migrating-applications-3-4"]
= Migrating your applications
include::_attributes/common-attributes.adoc[]
:context: migrating-applications-3-4
:migrating-applications-3-4:
toc::[]
You can migrate your applications by using the {mtc-full} ({mtc-short}) web console or from the xref:../migrating_from_ocp_3_to_4/advanced-migration-options-3-4.adoc#migrating-applications-cli_advanced-migration-options-3-4[command line].
You can use stage migration and cutover migration to migrate an application between clusters:
* Stage migration copies data from the source cluster to the target cluster without stopping the application. You can run a stage migration multiple times to reduce the duration of the cutover migration.
* Cutover migration stops the transactions on the source cluster and moves the resources to the target cluster.
You can use state migration to migrate an application's state:
* State migration copies selected persistent volume claims (PVCs).
* You can use state migration to migrate a namespace within the same cluster.
Most cluster-scoped resources are not yet handled by {mtc-short}. If your applications require cluster-scoped resources, you might have to create them manually on the target cluster.
During migration, {mtc-short} preserves the following namespace annotations:
* `openshift.io/sa.scc.mcs`
* `openshift.io/sa.scc.supplemental-groups`
* `openshift.io/sa.scc.uid-range`
These annotations preserve the UID range, ensuring that the containers retain their file system permissions on the target cluster. There is a risk that the migrated UIDs could duplicate UIDs within an existing or future namespace on the target cluster.
include::modules/migration-prerequisites.adoc[leveloffset=+1]
[role="_additional-resources"]
[id="additional-resources-for-migration-prerequisites_{context}"]
=== Additional resources for migration prerequisites
* link:https://docs.openshift.com/container-platform/3.11/install_config/registry/securing_and_exposing_registry.html#exposing-the-registry[Manually exposing a secure registry for {product-title} 3]
* xref:../migrating_from_ocp_3_to_4/troubleshooting-3-4.adoc#migration-updating-deprecated-internal-images_troubleshooting-3-4[Updating deprecated internal images]
[id="migrating-applications-mtc-web-console_{context}"]
== Migrating your applications by using the {mtc-short} web console
You can configure clusters and a replication repository by using the {mtc-short} web console. Then, you can create and run a migration plan.
include::modules/migration-launching-cam.adoc[leveloffset=+2]
include::modules/migration-adding-cluster-to-cam.adoc[leveloffset=+2]
include::modules/migration-adding-replication-repository-to-cam.adoc[leveloffset=+2]
include::modules/migration-creating-migration-plan-cam.adoc[leveloffset=+2]
[role="_additional-resources"]
[id="additional-resources-for-persistent-volume-copy-methods_{context}"]
=== Additional resources
* xref:../migrating_from_ocp_3_to_4/about-mtc-3-4.adoc#file-system-copy-method_about-mtc-3-4[{mtc-short} file system copy method]
* xref:../migrating_from_ocp_3_to_4/about-mtc-3-4.adoc#snapshot-copy-method_about-mtc-3-4[{mtc-short} snapshot copy method]
include::modules/migration-running-migration-plan-cam.adoc[leveloffset=+2]
:migrating-applications-3-4!: