How to undo iptables-save? [closed]

Question

On a standard Ubuntu server have I done

vi /etc/sysctl.conf did I enable

net.ipv4.ip_forward=1

then executed

iptables -t nat -A POSTROUTING -j MASQUERADE
sysctl -p /etc/sysctl.conf

and then

iptables-save

but what I wanted to do was

iptables-save > /etc/iptables.up.rules

Question I assume iptables-save have overridden the default iptables rules, which was not what I wanted.

How do I undo that?

Answer 1

iptables-save just outputs your iptables rules into a savable format. If you didn't redirect the output into a file nothing should have changed.