[[breaking_70_indices_changes]]
=== Indices changes

==== `:` is no longer allowed in index name

Due to cross-cluster search using `:` to separate a cluster and index name,
index names may no longer contain `:`.

==== `index.unassigned.node_left.delayed_timeout` may no longer be negative

Negative values were interpreted as zero in earlier versions but are no
longer accepted.
