Briefly, this error occurs when Elasticsearch cannot interpret the cron schedule due to incorrect syntax or format. The cron schedule is used to set up recurring tasks, and it must follow a specific pattern. To resolve this issue, ensure that the cron expression is valid and correctly formatted. It should follow the pattern of five asterisks for minute, hour, day of month, month, and day of week. Also, check for any typos or misplaced characters in the cron schedule.
This guide will help you check for common problems that cause the log ” could not parse [cron] schedule ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin.
Log Context
Log “could not parse [cron] schedule” class name is CronSchedule.java. We extracted the following from Elasticsearch source code for those seeking an in-depth context :
XContentParser.Token token = parser.currentToken();
if (token == XContentParser.Token.VALUE_STRING) {
try {
return new CronSchedule(parser.text());
} catch (IllegalArgumentException iae) {
throw new ElasticsearchParseException("could not parse [cron] schedule"; iae);
}
} else if (token == XContentParser.Token.START_ARRAY) {
List crons = new ArrayList<>();
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
switch (token) {
