NetWorker：NDMP 还原失败并显示“Timeout reading”（读取超时）

大型 NDMP DAR 恢复失败。
执行大型 NDMP DAR 恢复时，恢复将失败，并显示以下错误：

42572:nsrndmp_recover:ssid'582506817': Timeout reading
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42589:nsrndmp_recover:ssid'582506817': reply message for sequence 8 is not received.
42590:nsrndmp_recover:ssid'582506817': Timeout to receive any message from server.
42596:nsrndmp_recover:ssid'582506817': data start recover: communication failure.
42849:nsrndmp_recover:ssid'582506817': Unable to start the NDMP restore process.
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42589:nsrndmp_recover:ssid'582506817': reply message for sequence 9 is not received.
42590:nsrndmp_recover:ssid'582506817': Timeout to receive any message from server.
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42572:nsrndmp_recover:ssid'582506817': Timeout reading
42589:nsrndmp_recover:ssid'582506817': reply message for sequence 10 is not received.
42590:nsrndmp_recover:ssid'582506817': Timeout to receive any message from server.
42596:nsrndmp_recover:ssid'582506817': data abort: communication failure.
42871:nsrndmp_recover:ssid'582506817': Error during File NDMP Extraction.
86724:nsrdsa_recover: DSA listening at: host '<backup server>', IP address '<ip address>', port '<port>'.
nsrdsa_recover : Aborted
42840:nsrndmp_recover:ssid'582506817': NDMP recover failed.
42880:nsrndmp_recover:ssid'582506817': Error during NDMP recover
16279:recover: NDMP retrieval: child failed with status of 1

RCA 未知，但是可能的 NetApp 限制读取 nlist。

建议始终将 DAR 恢复限制为较小的大小和较少的文件，以获得最佳性能。 

在这种情况下，尝试的恢复接近 500 GB 和超过 192,000 个文件。因此，这很可能是由于 NetApp 努力应对如此庞大的 nlist 

要解决此问题，请将 nlist 从 NetWorker 端通过使用 NSR_NDMP_RESTORE_LIMIT 变量。这位于 Dell NetWorkerfor Network Data Management Protocol 用户指南中。特定于 NetWorker 版本的文档可通过以下方式获得：适用于NetWorker的支持 |手册和文档 

将其拆分为 10,000 个文件的示例：
NSR_NDMP_RESTORE_LIMIT=10000

Linux：从提升的提示符处，编辑 /etc/environment。添加 NSR_NDMP_RESTORE_LIMIT=10000。
视窗：从管理员命令/PowerShell 提示符处： setx /m NSR_NDMP_RESTORE_LIMIT 10000