public void addConfigservers(List<Configserver> configservers) {
        this.configservers.addAll(configservers);
        if ( ! this.configservers.isEmpty()) {
            this.defaultConfigserver = configservers.get(0);
        }
        this.zooKeepersConfigProvider = new ZooKeepersConfigProvider(configservers);
    }
Returns the log server for this, or null if none
config-model/src/main/java/com/yahoo/vespa/model/admin/Admin.java