Hi Ganesh,
If you trying to send the Access-Log to LogRhythm, you can use custom client option to send it across as you do for any other SIEM tool. From what I can see, LogRhythm supports ELFF format which means you don't need to make any changes in the default log formats of ASG to make it work.
For configuration, refer: https://support.symantec.com/en_US/article.TECH242216.html