This KB is regarding Static Host Mapping in SRX and how to configure it on SRX .
Static Host Mapping in SRX is to configured .
For the configuration of Static host mapping in SRX here is document that will be useful -
https://www.juniper.net/documentation/us/en/software/junos/cli-reference/topics/ref/statement/static-host-mapping-edit-system.html
For adding static DNS mappings in SRX devices- https://supportportal.juniper.net/s/article/SRX-How-to-add-static-DNS-mappings-in-SRX?language=en_US