final Http2SolrClient.Builder scb = new Http2SolrClient.Builder(RequiredOpts.sourceUrl);
    final Http2SolrClient.Builder thb = new Http2SolrClient.Builder();

    if (!sourceH2) {
      scb.useHttp1_1(true);
    }

    if (!targetH2) {
      thb.useHttp1_1(true);
    }

    if (sourceUser != null && !sourceUser.equals("")) {
      log.info("Setting source credentials");
      scb.withBasicAuthCredentials(sourceUser, sourcePass);
    }
    if (targetUser != null && !targetUser.equals("")) {
      log.info("Setting target credentials");
      thb.withBasicAuthCredentials(targetUser, targetPass);
    }

    final CloudHttp2SolrClient.Builder tcb = new CloudHttp2SolrClient.Builder(targetZkHosts,
        chroot);
    log.info("Building Http2SolrClient for target CloudHttp2SolrClient");
    final Http2SolrClient thc = thb.build();
    tcb.sendDirectUpdatesToShardLeadersOnly().withHttpClient(thc);
    final long nanoStart;
    final ArrayBlockingQueue<SolrInputDocument> queue;
    log.info("Building remaining SolrClients");
    final SolrClient sourceClient = scb.build();
    final SolrClient targetClient = tcb.build();