One cause for "iptables: No chain/target/match by that name" on Ubuntu
I couldn't successfully execute a simple iptables command and got this error on an Ubuntu server:
# /sbin/iptables -I INPUT ....
iptables: No chain/target/match by that name
The cause was that two modules weren't loaded: xt_multiport and xt_comment. Normally Ubuntu loads them automatically, but not this time due to another problem.
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