Basic sanity check: Verify Node 1 is up and working.

基本的状态检查：验证节点1正常工作。

youdao

The program needs to check and see if the current node is the NULL list.

程序需要检查确认当前节点是否为NULL列表。

youdao

The program needs to check and see if the current node is the NULL list.

程序需要检查确认当前节点是否为NULL列表。

youdao