def hosts=[]
def TARGETLEVEL="L2"
def UC_CM_ID="CM"monospaced text

script
{
START_SERVER_LIST2.each
{
CURRENT_END_HOST="${it}".trim()
END_SHORT_HOST="${CURRENT_END_HOST}".substring(0,"${CURRENT_END_HOST}".indexOf("."))
CREDENTIAL_ID="$TARGETLEVEL""""$UC_CM_ID""""${END_SHORT_HOST}"
hosts.add("${CREDENTIAL_ID}")

}
def servers = START_SERVER_LIST2
def projectsBuilds = [:]
for (int j=0; j<=5;j++)
{
def currentServer = START_SERVER_LIST2.get(j)
projectsBuilds[currentServer] = {

stage(String.format('%s execution', 'Checkout on'+currentServer))
{

def TAGNAME="TEST"
def SOURCE_BRANCH_NAME="main"
def TARGET_BRANCH_NAME="main"
def SAVE_FILE_PATH="/tmp"
def UTILITY_SCRIPT_DIR="/tmp"
def level_name="L2"
def user_name="cm"

CURRENT_END_SERVER="${currentServer}".trim()
END_SHORT_HOSTNAME="${CURRENT_END_SERVER}".substring(0,"${CURRENT_END_SERVER}".indexOf("."))
END_CM_USER_CREDENTIAL_ID="$TARGETLEVEL""""$UC_CM_ID""""${END_SHORT_HOSTNAME}"
echo "END_CM_USER_CREDENTIAL_ID=$END_CM_USER_CREDENTIAL_ID"
sshagent(credentials: ["${END_CM_USER_CREDENTIAL_ID}""])

{ echo "currentServer=$currentServer" echo "END_SHORT_HOSTNAME=$END_SHORT_HOSTNAME" sh """ echo "$user_name"; echo $full_host_name; #ssh -oStrictHostKeyChecking=no -oBatchMode=yes -oLogLevel=error -oUserKnownHostsFile=/dev/null $user_name@$full_host_name /bin/ksh <<EOF """ }

}
}

}
echo "Parallel builds"
print(projectsBuilds)
parallel projectsBuilds;
}

we are creating stages dynamically based on the START_SERVER_LIST2 parameter. Created stages running parallelly except sshagent block. When sshagent starts its execution parallely it runs for only last server of START_SERVER_LIST2 parameter.

Is sshagent blocks paralllel mechanism?
how to run sshagent parallely for different servers?
how to pass different parameter values for sshagent block?