运行这部分代码时出现错误，希望大神们解答一下，谢谢！

# Setup cluster
clust <- makeCluster(no_cores) #This line will take time
clusterExport(clust, c("estNRI_Fine","crr","get_probs"))
#The parallel version of lapply() is parLapply() and needs an additional cluster argument.
boot.est=parLapply(clust,1:nboot, gene)

stopCluster(clust)

错误是：

Error in checkForRemoteErrors(val) :    12 nodes produced errors; first error: 无法打开链结