Question : executing commands after telnetting to a server on listening defined port

The server is listening on port 7777, for example, and there are many self-defined commands. When I execute the sequences of the commands manually it works fine i.e:
1. telnet to myserver with port 7777 then press Enter
2. execute authentication command (login) to the server (successfully)
3. execute the predefined command, the result output (response from the server) is displayed (successfully)

I want to automate this task by deciding to write a task based on Bash shell script programming. I fail to achieve my goal with the scripts as shown in code snippet below. Please check my codes and have your comments. Thanks

Code Snippet:

         
           
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             #================
#First Coding
#=================
#!/bin/bash
 
SRV_HOST="myserver"
SRV_PORT="7777"
SRV_USER="SrvUser"
SRV_PASSWORD="SrvPassword"
 
telnet $SRV_HOST $SRV_PORT
command1
command2
 
#================
#Second Coding
#================
#!/bin/bash
 
SRV_HOST="myserver"
SRV_PORT="7777"
SRV_USER="SrvUser"
SRV_PASSWORD="SrvPassword"
 
telnet $SRV_HOST $SRV_PORT <<-EOF
command1
command2
EOF

           
         

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Answer : executing commands after telnetting to a server on listening defined port

I found a command to successfully connect to the remote server using specified port and execute the commands. Please refer to the code snippet

                       
         
           
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             #!/bin/bash
set -o verbose
shopt -o -s no unset
 
SRVT_HOS="myserver"
SRV_PORT="7777"
SRV_USER="SrvUser"
SRV_PASSWORD="SrvPassword"
 
printf "Connecting to host $SRV_HOST\r\n"
exec 3<> /dev/tcp/$SRVT_HOS/$SRV_PORT   #Number 3 is the file descriptor (fd)
printf "command1\r\n" >&3
printf "command2\r\n" >&3
 
#To display the output when getting response from the server
while read LINE <&3 ; do
    printf "%s\n" "$LINE"
done
 
exec 3>&-       #Close fd 3

           
         

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