1This setting may be a valid {ref}/date-math-index-names.html[Elasticsearch date math string]. 2 3A date math name takes the following form: 4 5[source,sh] 6------------- 7<static_name{date_math_expr{date_format|time_zone}}> 8------------- 9 10[width="50%", cols="<m,"] 11|=== 12|static_name| is the static text part of the name 13|date_math_expr| is a dynamic date math expression that computes the date dynamically 14|date_format|is the optional format in which the computed date should be rendered. Defaults to `YYYY.MM.dd`. 15|time_zone|is the optional time zone . Defaults to `utc`. 16|=== 17 18The following example shows different forms of date math names and the final form they resolve to given the current time is 22rd March 2024 noon utc. 19 20[width="50%", cols="<m,m", options="header"] 21|=== 22|Expression| Resolves to 23|<logstash-{now/d}>| logstash-2024.03.22 24|<logstash-{now/M}>| logstash-2024.03.01 25|<logstash-{now/M{YYYY.MM}}>| logstash-2024.03 26|<logstash-{now/M-1M{YYYY.MM}}>| logstash-2024.02 27|<logstash-{now/d{YYYY.MM.dd\|+12:00}}> | logstash-2024.03.23 28|===