TCP connections to itself?

Elastic Stack Elasticsearch
1

Is it normal for ES to open many connections to itself? I'm on ES version 6.1.1. I have 3 machines in a cluster (internal IPs are: 172.16.2.4, 2.5 and 2.6). Is it normal for all of the 127.0.0.1 connections to itself?When doing netstat -aon, I see about 100 entries that look like this:

Proto  Local Address          Foreign Address        State           PID
TCP    127.0.0.1:9200         127.0.0.1:60324        ESTABLISHED     10160
TCP    127.0.0.1:59300        127.0.0.1:59301        ESTABLISHED     10160
TCP    127.0.0.1:59301        127.0.0.1:59300        ESTABLISHED     10160
TCP    127.0.0.1:59302        127.0.0.1:59303        ESTABLISHED     10160
TCP    127.0.0.1:59303        127.0.0.1:59302        ESTABLISHED     10160
TCP    127.0.0.1:59304        127.0.0.1:59305        ESTABLISHED     10160
TCP    127.0.0.1:59305        127.0.0.1:59304        ESTABLISHED     10160
TCP    127.0.0.1:59306        127.0.0.1:59307        ESTABLISHED     10160
TCP    127.0.0.1:59307        127.0.0.1:59306        ESTABLISHED     10160
TCP    127.0.0.1:59308        127.0.0.1:59309        ESTABLISHED     10160
TCP    127.0.0.1:59309        127.0.0.1:59308        ESTABLISHED     10160
TCP    127.0.0.1:59310        127.0.0.1:59311        ESTABLISHED     10160
TCP    127.0.0.1:59311        127.0.0.1:59310        ESTABLISHED     10160
TCP    127.0.0.1:59312        127.0.0.1:59313        ESTABLISHED     10160
TCP    127.0.0.1:59313        127.0.0.1:59312        ESTABLISHED     10160
TCP    127.0.0.1:59314        127.0.0.1:59315        ESTABLISHED     10160
TCP    127.0.0.1:59315        127.0.0.1:59314        ESTABLISHED     10160
TCP    127.0.0.1:59316        127.0.0.1:59317        ESTABLISHED     10160
TCP    127.0.0.1:59317        127.0.0.1:59316        ESTABLISHED     10160
TCP    127.0.0.1:59318        127.0.0.1:59319        ESTABLISHED     10160
TCP    127.0.0.1:59319        127.0.0.1:59318        ESTABLISHED     10160
TCP    127.0.0.1:59320        127.0.0.1:59321        ESTABLISHED     10160
TCP    127.0.0.1:59321        127.0.0.1:59320        ESTABLISHED     10160
TCP    127.0.0.1:59322        127.0.0.1:59323        ESTABLISHED     10160
TCP    127.0.0.1:59323        127.0.0.1:59322        ESTABLISHED     10160
TCP    127.0.0.1:59324        127.0.0.1:59325        ESTABLISHED     10160
TCP    127.0.0.1:59325        127.0.0.1:59324        ESTABLISHED     10160
TCP    127.0.0.1:59326        127.0.0.1:59327        ESTABLISHED     10160
TCP    127.0.0.1:59327        127.0.0.1:59326        ESTABLISHED     10160
TCP    127.0.0.1:59328        127.0.0.1:59329        ESTABLISHED     10160
TCP    127.0.0.1:59329        127.0.0.1:59328        ESTABLISHED     10160
TCP    127.0.0.1:59330        127.0.0.1:59331        ESTABLISHED     10160
TCP    127.0.0.1:59331        127.0.0.1:59330        ESTABLISHED     10160
TCP    127.0.0.1:59332        127.0.0.1:59333        ESTABLISHED     10160
TCP    127.0.0.1:59333        127.0.0.1:59332        ESTABLISHED     10160
TCP    127.0.0.1:59334        127.0.0.1:59335        ESTABLISHED     10160
TCP    127.0.0.1:59335        127.0.0.1:59334        ESTABLISHED     10160
TCP    127.0.0.1:59336        127.0.0.1:59337        ESTABLISHED     10160
TCP    127.0.0.1:59337        127.0.0.1:59336        ESTABLISHED     10160
TCP    127.0.0.1:59338        127.0.0.1:59339        ESTABLISHED     10160
TCP    127.0.0.1:59339        127.0.0.1:59338        ESTABLISHED     10160
TCP    127.0.0.1:59340        127.0.0.1:59341        ESTABLISHED     10160
TCP    127.0.0.1:59341        127.0.0.1:59340        ESTABLISHED     10160
TCP    127.0.0.1:59342        127.0.0.1:59343        ESTABLISHED     10160
TCP    127.0.0.1:59343        127.0.0.1:59342        ESTABLISHED     10160
TCP    127.0.0.1:59344        127.0.0.1:59345        ESTABLISHED     10160
TCP    127.0.0.1:59345        127.0.0.1:59344        ESTABLISHED     10160
TCP    127.0.0.1:59346        127.0.0.1:59347        ESTABLISHED     10160
TCP    127.0.0.1:59347        127.0.0.1:59346        ESTABLISHED     10160
TCP    127.0.0.1:59348        127.0.0.1:59349        ESTABLISHED     10160
TCP    127.0.0.1:59349        127.0.0.1:59348        ESTABLISHED     10160
TCP    127.0.0.1:59350        127.0.0.1:59351        ESTABLISHED     10160
TCP    127.0.0.1:59351        127.0.0.1:59350        ESTABLISHED     10160
TCP    127.0.0.1:59352        127.0.0.1:59353        ESTABLISHED     10160
TCP    127.0.0.1:59353        127.0.0.1:59352        ESTABLISHED     10160
TCP    127.0.0.1:59354        127.0.0.1:59355        ESTABLISHED     10160
TCP    127.0.0.1:59355        127.0.0.1:59354        ESTABLISHED     10160
TCP    127.0.0.1:59356        127.0.0.1:59357        ESTABLISHED     10160
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