documentclass{article}
usepackage{xcolor}
usepackage{listings}
usepackage{float}
usepackage{tikz}
usepackage{siunitx}
usetikzlibrary{arrows,decorations.pathmorphing,backgrounds,positioning,fit,petri}

definecolor{mycolor}{RGB}{31,22,70}
definecolor{mycolor2}{RGB}{21,126,251}
begin{document}
       begin{figure}[H]
        centering
        begin{tikzpicture}[
            scale=0.8,
            transform shape,
            show background rectangle,
            background rectangle/.style={fill=gray!10},
            box/.style={draw, font=itshape}
            ]
            coordinate (b) at (current page.center);
            node[rounded corners=3mm, label=center:{Onboard}, fill=mycolor2!20] (onboard)at (b) [draw,minimum width=2.5cm,minimum height=2.4cm] {};

            node[below right = of onboard, rounded corners=3mm, label=center:{Deploy}, fill=mycolor2!20] (deploy) [draw,minimum width=2.5cm,minimum height=2.4cm] {};

            node[below right = of deploy,rounded corners=3mm, label=center:{Monitor}, fill=mycolor2!20] (monitor) [draw,minimum width=2.5cm,minimum height=2.4cm] {};

            node[below left = of monitor, rounded corners=3mm, label=center:{Scale}, fill=mycolor2!20] (scale) [draw,minimum width=2.5cm,minimum height=2.4cm] {};

            node[left =of scale, rounded corners=3mm, label=center:{healing/fault-recovery}, fill=mycolor2!20] (healing) [draw,minimum width=4cm,minimum height=2.4cm] {};

            node[above left = of healing, rounded corners=3mm, label=center:{Update}, fill=mycolor2!20] (update)[draw,minimum width=2.5cm,minimum height=2.4cm] {};

            node[above =of update, rounded corners=3mm, label=center:{Undeploy}, fill=mycolor2!20] (undeploy) [draw,minimum width=2.5cm,minimum height=2.4cm] {};
            draw[thick, mycolor](onboard)--(deploy);
            draw[thick, mycolor](deploy)--(monitor);
            draw[thick, mycolor](monitor)--(scale);
            draw[thick, mycolor](scale)--(healing);
            draw[thick, mycolor](healing)--(update);
            draw[thick, mycolor](update)--(undeploy);
            draw[thick, mycolor,->](undeploy)--(onboard);
           end{tikzpicture}
        caption{xxx}
    end{figure}

end{document}