Content cannot be published

Description description

One of our customers is complaining that their Stage publisher is not working properly and they cannot publish content on this instance and the following errors could be seen in error.log:

20.09.2022 06:53:27.635 *INFO* discovery.connectors.common.runner.a00e3ce0-3925-4755-990b-f2d776738269.discoveryLiteCheck org.apache.sling.discovery.base.commons.BaseDiscoveryService getTopology: undefined cluster view: REPOSITORY_EXCEPTION org.apache.sling.discovery.base.commons.UndefinedClusterViewException: Exception while processing descriptor: java.lang.IllegalArgumentException: Can't create child on a synthetic root
20.09.2022 06:53:29.636 *ERROR* discovery.connectors.common.runner.a00e3ce0-3925-4755-990b-f2d776738269.discoveryLiteCheck org.apache.sling.discovery.oak.cluster.OakClusterViewService getLocalClusterView: repository exception: java.lang.IllegalArgumentException: Can't create child on a synthetic root
java.lang.IllegalArgumentException: Can't create child on a synthetic root
at org.apache.sling.resourceresolver.impl.ResourceResolverImpl.create(ResourceResolverImpl.java:979) org.apache.sling.resourceresolver:1.7.2.B0001
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResourceInternal(ResourceUtil.java:666) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:603) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:571) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResourceInternal(ResourceUtil.java:654) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:603) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:571) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResourceInternal(ResourceUtil.java:654) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:603) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:571) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResourceInternal(ResourceUtil.java:654) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:603) org.apache.sling.api:2.22.0
at org.apache.sling.api.resource.ResourceUtil.getOrCreateResource(ResourceUtil.java:571) org.apache.sling.api:2.22.0
at org.apache.sling.discovery.commons.providers.util.ResourceHelper.getOrCreateResource(ResourceHelper.java:45) org.apache.sling.discovery.commons:1.0.20
at org.apache.sling.discovery.commons.providers.spi.base.IdMapService.readIdMap(IdMapService.java:302) org.apache.sling.discovery.commons:1.0.20
at org.apache.sling.discovery.commons.providers.spi.base.IdMapService.toSlingId(IdMapService.java:280) org.apache.sling.discovery.commons:1.0.20
at org.apache.sling.discovery.oak.cluster.OakClusterViewService.asClusterView(OakClusterViewService.java:174) org.apache.sling.discovery.oak:1.2.22
at org.apache.sling.discovery.oak.cluster.OakClusterViewService.getLocalClusterView(OakClusterViewService.java:120) org.apache.sling.discovery.oak:1.2.22
at org.apache.sling.discovery.base.commons.BaseDiscoveryService.getTopology(BaseDiscoveryService.java:77) org.apache.sling.discovery.base:2.0.8
at org.apache.sling.discovery.oak.OakDiscoveryService.checkForTopologyChange(OakDiscoveryService.java:660) org.apache.sling.discovery.oak:1.2.22
at org.apache.sling.discovery.oak.pinger.OakViewChecker.discoveryLiteCheck(OakViewChecker.java:217) org.apache.sling.discovery.oak:1.2.22
at org.apache.sling.discovery.oak.pinger.OakViewChecker.access$000(OakViewChecker.java:62) org.apache.sling.discovery.oak:1.2.22
at org.apache.sling.discovery.oak.pinger.OakViewChecker$1.run(OakViewChecker.java:193) org.apache.sling.discovery.oak:1.2.22
at org.apache.sling.discovery.base.commons.PeriodicBackgroundJob.safelyRun(PeriodicBackgroundJob.java:86) org.apache.sling.discovery.base:2.0.8
at org.apache.sling.discovery.base.commons.PeriodicBackgroundJob.run(PeriodicBackgroundJob.java:77) org.apache.sling.discovery.base:2.0.8
at java.base/java.lang.Thread.run(Thread.java:834)

Resolution resolution

The error in the log is not related to caching, but they appear when the service user does not have the right permissions for the path /var/discovery either on the Author or on the Publisher.

Upon further investigation, while asking the customer to verify the permissions for the /var/discovery path it was found that on the Stage publisher there was no “discovery” folder under /var and there was a lot of missing content as well.

While the /var folder on the Production publisher had more than 20 children, the /var folder on the Stage publisher only had 2 - “replication” and “sling”.

The issue was fixed after replicating the /var/structure from Production to Stage and restarting the AEM on Stage Publishers.

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