Delaying allocation for unassigned shards next check in – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 2.3-2.3

Briefly, this error occurs when Elasticsearch is unable to allocate shards to nodes due to insufficient resources, node failures, or configuration issues. It’s delaying the allocation to avoid unnecessary shard movements. To resolve this, you can increase the cluster’s resources, check for failed nodes and fix them, or adjust the shard allocation settings. Also, ensure that the cluster health is green and that there are no network connectivity issues. If the problem persists, consider re-indexing the data or increasing the number of nodes in the cluster.

This guide will help you check for common problems that cause the log ” delaying allocation for [{}] unassigned shards; next check in [{}] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: allocation, cluster and routing.

Log Context

Log “delaying allocation for [{}] unassigned shards; next check in [{}]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

} else if (minDelaySetting  0 : "next delay must be non 0 as minDelaySetting is [" + minDelaySetting + "]";
      "delaying allocation for [{}] unassigned shards; next check in [{}]";
                        UnassignedInfo.getNumberOfDelayedUnassigned(event.state()); nextDelay);
                registeredNextDelayFuture = threadPool.schedule(nextDelay; ThreadPool.Names.SAME; new AbstractRunnable() {
                    protected void doRun() throws Exception {
                        minDelaySettingAtLastSchedulingNanos = Long.MAX_VALUE;


How helpful was this guide?

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?