Jmeter simulating traffic and avoiding 429
Given that this is symptomatic of rate limiting in Nginx in this case, the solution is to configure the rate limiting feature of Nginx to allow this

A whitelist could  be created in the configuration to remove ratelimiting from the url generating the traffic.

To follow the Nginx documentation, this could be specified as whitelisting an IP.

The current server setup is : 

limit_req_zone $binary_remote_addr zone=flood:10m rate=12r/s;
limit_req_zone $binary_remote_addr zone=bot:10m rate=200r/m;
limit_req_status 429;
limit_conn_zone $binary_remote_addr zone=connperip:10m;
limit_conn_status 429;


This sets up the rate limit on connections. A whitelist can be created as suggested above, by simulating a boolean condition with a key value map:

geo $limit {
    default 1;
    10.0.0.0/8 0;
    192.168.0.0/24 0;
}

map $limit $limit_key {
    0 "";
    1 $binary_remote_addr;
}


This removes the rate limit (sets it to 0) if the remote address falls into the whitelist:

limit_req_zone $limit_key zone=req_zone:10m rate=5r/s;

server {
    location / {
        limit_req zone=req_zone burst=10 nodelay;