1
this is how I logged in

ssh $SERVERUSERNAME@$SERVERIPV4-p $SERVERPORT < < serveraction
~ Code ~

serveraction

the result window always prompts
Pseudo-terminal will not be allocated because stdin is not a terminal.

what does this mean?
do I have to have this?

/ dev/null 2 > & 1?

adding-t to update: has no effect.

2 requires administrator privileges during code execution,
but the waiting time for me to enter my password is so short that it almost skips it.
then come out of this picture, what is the reason?

Password: su: Authentication failure

come out first. Password:, cursor flashes there for seven or eight seconds and su: Authentication failure comes out immediately

my code is either su-root-s / home/$SERVERUSERNAME/Documents/scripts/centos7/centos7_server1.sh, or

< H1 > su-root < < EOF < / H1 > < H1 > bash / home/$SERVERUSERNAME/Documents/scripts/centos7/centos7_server1.sh < / H1 > < H1 > bash / home/$SERVERUSERNAME/Documents/scripts/centos7/centos7_server2.sh < / H1 > < H1 > EOF < / H1 >

the server forbids root login, but manual remote login can switch to root

.

Thank you all

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