How do I specify a subnet mask when adding a rule in nftables?

Question

1.6k views Asked by Mithokai At 09 December 2019 at 15:38

How does one specify the subnet mask when adding a rule in nftables?

A slash immediately following the specified ip address results in a syntax error.

nft add rule ip filter input 0.0.0.0/24 drop

results in

Error: syntax error, unexpected /

(OS: Debian Buster: nftables v0.9.0)

There are 1 answers

**Qwertz** · Accepted Answer · 2020-01-29 12:50:03

Qwertz On 29 January 2020 at 12:50 BEST ANSWER

Your syntax isn't quite right. You are missing "ip saddr" after input.

nft add rule ip filter input ip saddr 0.0.0.0/24 drop