mongoimport error - Failed: error connecting to db server: no reachable servers
I have gone through the error and checked out, the problem is resist with mongoimport syntax. The mongoimport shell is unable to find the location of (.json) file.

And also there is mistake like --jsonArray.

As per MongoDB BOL --jsonArray Modifies the output of mongoexport to write the entire contents of the export as a single JSON array. By default mongoexport writes data using one JSON document for every MongoDB document.  


  Note:- Accepts the import of data expressed with multiple MongoDB documents within a single JSON array. Limited to imports
  of 16 MB or smaller.


For Simple mongoimport syntax will be like that

mongoimport -d databasename -c collectionname (File Location of json file.json)


For Example

mongoimport -d test -c zips C:\MongoDBDBA\zips.json

2018-02-07T08:32:31.084+0300    connected to: localhost
2018-02-07T08:32:31.532+0300    imported 29353 documents


IN the above mongoimport syntax the database name is test and collection name is zips and C:\MongoDBDBA\zips.json is the (.json) file location.

For Example with localhost and port number 27017

If you want to use localhost and by default port number 27017 in mongoimport then simply the syntax will be like that

mongoimport --host localhost --port 27017 -d blog -c posts C:\MongoDBDBA\posts.json

2018-02-07T10:48:54.340+0300    connected to: localhost:27017
2018-02-07T10:48:56.333+0300    [########################] blog.posts   33.9MB/33.9MB (100.0%)
2018-02-07T10:48:56.345+0300    [########################] blog.posts   33.9MB/33.9MB (100.0%)
2018-02-07T10:48:56.346+0300    imported 1000 documents


Here in the above syntax blog is the database name and collection name is posts.


  Most Important Note:- Run mongoimport from the system command line, not the mongo shell.


For your further ref Here