Actually, you are getting 4 messages in your syslog for each single message.
...and the way you have syslog.conf configured, that is to be expected.
You only need the -lowest- logging level specified. Since you have all but debuggging specified, you are getting 6-N+1 copies of your message, where N is the severity level of the message.
In this instance you are showing us a link-down (sev 3) message - which corresponds to "err", so you got one message for the config line "local7.info", one for "local7.notice", one for "local7.warning" and one for "local7.err" - all of which went to /var/adm/internet-gw.log.
Just remove all the entries but local7.info and that should fix it.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...