Here's a config with Westhash as primary and Nicehash as fail-over:

{
  "pools": [
    {
      "url": "stratum+tcp://stratum.westhash.com:3333/#xnsub#skipcbcheck",
      "user": "

",
      "pass": ",d=16384"
    },
    {
      "url": "stratum+tcp://stratum.nicehash.com:3333/#xnsub#skipcbcheck",
      "user": "

",
      "pass": ",d=16384"
    }
  ],
  "failover-only": true,
  "scrypt-n": 10
}