Modified the netcat Configuration to Include the -N option, which is required by more recent versions of netcat. The option allows the shutdown of the network socket after the input EOF.

I see that socat is using too much of CPU when copying data, so I wanted to try nc

When I do it the transfer fails with

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2020-01-11T17:18:35.697124Z 2 [Note] WSREP: GCache history reset: 00000000-0000-0000-0000-000000000000:0 -> 22d3399d-33f5-11ea-acfb-7680212432b5:155271
2020-01-11T17:18:37.761146Z 0 [Note] WSREP: (654e68b9, 'tcp://0.0.0.0:4567') turning message relay requesting off
2020-01-11T17:20:15.291614Z WSREP_SST: [ERROR] ******************* FATAL ERROR ********************** 
 2020-01-11T17:20:15.294060Z WSREP_SST: [ERROR] Possible timeout in receving first data from donor in gtid/keyring stage
 2020-01-11T17:20:15.296373Z WSREP_SST: [ERROR] ****************************************************** 
 2020-01-11T17:20:15.299271Z WSREP_SST: [ERROR] Cleanup after exit with status:32
2020-01-11T17:20:15.332641Z 0 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '172.16.0.3' --datadir '/mnt/data/pxc-5.7.28/' --defaults-file '/opt/vadim/servers/my.cnf' --defaults-group-suffix '' --parent '1496' --mysqld-version '5.7.28-31-31.41' '' : 32 (Broken pipe)
2020-01-11T17:20:15.332703Z 0 [ERROR] WSREP: Failed to read uuid:seqno from joiner script.
2020-01-11T17:20:15.332718Z 0 [ERROR] WSREP: SST script aborted with error 32 (Broken pipe)

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in my.cnf I use

[sst]
 encrypt=0
 backup_threads=1
 transferfmt=nc