verificando se o iptables está definido em um sistema no script [duplicado]

Estou escrevendo um script no bash e preciso verificar se o iptables está definido...

if [ `iptables-save | grep '^\-' | wc -l` > 0 ]
then
    echo "Iptables already set, skipping..........!"
else
    Here the iptables get set

Mas não está funcionando como esperado....

PROBLEMA:

Eu fiz iptables-savee ele criou isso:

$iptables-save
# Generated by iptables-save v1.6.0 on Tue Oct 16 02:48:41 2018
*filter
:INPUT ACCEPT [2:266]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [2:116]
COMMIT
# Completed on Tue Oct 16 02:48:41 2018

Então, se eu executar o teste, ele descobre que eles já estão definidos .... como aqui:

(root@notemDEB78)-(03:12:20)-(/home/something78/Bash_Programming_2018)
$s.sh
Iptables already set....skipping!!!!!
(root@notemDEB78)-(03:12:25)-(/home/something78/Bash_Programming_2018)
$iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination 

(root@notemDEB78)-(03:16:41)-(/home/something78/Bash_Programming_2018)
$iptables-save | grep '^\-' | wc -l
0

PERGUNTA:

• Por que sempre descobre que o iptables está definido quando o obviamente não está

• Você tem uma maneira melhor/funcional de verificar se iptablesestá definido .... meu sistema éDebian 9

  bash -versão GNU bash, versão 4.4.12(1)-release (x86_64-pc-linux-gnu) Copyright (C) 2016 Free Software Foundation, Inc. Licença GPLv3+: GNU GPL versão 3 ou posterior http://gnu. org/licenses/gpl.html

QUANTO À POSSÍVEL DUPLICATA:

Esta pergunta também está perguntando se alguém tem uma maneira melhor de verificar se o iptables está definido para um script no bash ....

EDITAR:

Por set quero dizer que o iptables foi configurado assim:

if [[ `iptables-save | grep '^\-' | wc -l` > 0 ]]
    then
        echo "Iptables already set....skipping!!!!!"
    else
        if [ "$PORT" = "" ]
        then
            echo "Port not set for iptables exiting"
            echo -n "Setting port now, insert portnumber: "
            read port
            PORT=$port
        fi
        if [ ! -f /etc/iptables.test.rules ]
        then
            touch /etc/iptables.test.rules
        else
            cat /dev/null > /etc/iptables.test.rules
        fi

        cat << EOT >> /etc/iptables.test.rules
        *filter

        # Allows all loopback (lo0) traffic and drop all traffic to 127/8 that doesn't use lo0
        -A INPUT -i lo -j ACCEPT
        -A INPUT ! -i lo -d 127.0.0.0/8 -j REJECT

        # Accepts all established inOAUTH_TOKEN=d6637f7ccf109a0171a2f55d21b6ca43ff053616bound connections
        -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

        # Allows all outbound traffic
        # You could modify this to only allow certain traffic
        -A OUTPUT -j ACCEPT

        # Allows HTTP and HTTPS connections from anywhere (the normal ports for websites)
        -A INPUT -p tcp --dport 80 -j ACCEPT
        -A INPUT -p tcp --dport 443 -j ACCEPT

        # Allows SSH connections
        # The --dport number is the same as in /etc/ssh/sshd_config
        -A INPUT -p tcp -m state --state NEW --dport $PORT -j ACCEPT

        # Now you should read up on iptables rules and consider whether ssh access
        # for everyone is really desired. Most likely you will only allow access from certain IPs.

        # Allow ping
        #  note that blocking other types of icmp packets is considered a bad idea by some
        #  remove -m icmp --icmp-type 8 from this line to allow all kinds of icmp:
        #  https://security.stackexchange.com/questions/22711
        -A INPUT -p icmp -m icmp --icmp-type 8 -j ACCEPT

        # log iptables denied calls (access via dmesg command)
        -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7

        # Reject all other inbound - default deny unless explicitly allowed policy:
        -A INPUT -j REJECT
        -A FORWARD -j REJECT

        COMMIT
EOT
        sed "s/^[ \t]*//" -i /etc/iptables.test.rules ## remove tabs and spaces
        /sbin/iptables-restore < /etc/iptables.test.rules || echo "iptables-restore failed"; exit 127
        /sbin/iptables-save > /etc/iptables.up.rules || echo "iptables-save failed"; exit 127
        printf "#!/bin/bash\n/sbin/iptables-restore < /etc/iptables.up.rules" > /etc/network/if-pre-up.d/iptables ## create a script to run iptables on startup
        chmod +x /etc/network/if-pre-up.d/iptables || echo "cmod +x failed"; exit 127
    fi