The cluster crashed in sample database

I have built a cluster including 3 nodes on HDD with yugabytedb in 2.0.10 version. the cluster started well. I want to ask for help.
Q1:I connected local node database by psql with default user yugabyte and password, but I find the connection time is too long. I waited about 1 min to connect successfully. Why it is so slow?
Q2: I logged in the db, I create database and import tables basing on the user docs. When the import SQL script was running,the connection was closed unexpectedly.
the node returned info :
> ysqlsh: sample/sportsdb_inserts.sql:2: server closed the connection unexpectedly
> This probably means the server terminated abnormally
> before or while processing the request.
> ysqlsh:sample/sportsdb_inserts.sql:2: connection to server was lost
When I tried to connect again, the node returned info :
> psql: could not connect to server: Connection refused
> Is the server running on host “localhost” (127.0.0.1) and accepting
> TCP/IP connections on port 5433?
> could not connect to server: No route to host
> Is the server running on host “localhost” (::1) and accepting
> TCP/IP connections on port 5433?
I used ps x command to check process ,and found all of the nodes in the cluster had crashed.
Why? How to update some starting parameters?

Hi @harryboot,
We are not optimized for HDDs and as such will have slower performance compared to SSDs.

Q1: While establishing YSQL connection, we load the catalog cache from master and this seems to be slow for your setup. We are working on this : [YSQL] Optimize session initialization for multi-region deployment · Issue #3049 · yugabyte/yugabyte-db · GitHub and should have improved performance by end of February/mid March.

Q2: Can you check tserver logs to see what went wrong? Logs will be available at /disk-1/yb-data/tserver/logs folder.