Add series file compaction warning to enterprise 1.11.3 release notes (#5245)

* add warning to enterprise 1.11.3 release notes, closes influxdata/DAR#406

* Update content/enterprise_influxdb/v1/about-the-project/release-notes.md

content/enterprise_influxdb/v1/about-the-project/release-notes.md

@@ -21,6 +21,26 @@ InfluxDB Enterprise builds are available. For more information, see
 [FIPS-compliant InfluxDB Enterprise builds](/enterprise_influxdb/v1/introduction/installation/fips-compliant/).
 {{% /note %}}
 
+{{% warn %}}
+#### Series file compaction on start-up
+
+With InfluxDB Enterprise v1.11.3+, on start-up, InfluxDB run the
+`influxd_inspect -compact-series-file` command to [compact series files](/enterprise_influxdb/v1/tools/influx_inspect/#--compact-series-file-) before data nodes are started.
+Series files are stored in `_series` directories in the
+[`/data` directory](/enterprise_influxdb/v1/concepts/file-system-layout/#data-node-file-system-layout)
+(default is `/var/lib/data/<db-name>/_series`).
+
+- If any series files are corrupt, the `influx_inspect` or `influxd` processes on
+  the data node may fail to start. In both cases, delete the series file
+  directories before restarting the database. InfluxDB will automatically
+  regenerate the deleted series files when the database is restarted.
+- To check if series files are corrupt before starting the database, run the
+  [`influx_inspect verify-seriesfile` command](/enterprise_influxdb/v1/tools/influx_inspect/#verify-seriesfile)
+  while the database is off-line.
+- If series files are large (20+ gigabytes), it may also be faster to delete the
+  series file directories before starting the database.
+{{% /warn %}}
+
 ### Bug Fixes
 
 - Surround binary expressions in parenthesis.