Issue with firewall rules on mx75 with 16.16

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Issue with firewall rules on mx75 with 16.16

Getting a really weird issue on MX75s with firewall rules. if i change/amend or reorder firewall rules it seems to stop all rules working. If i have an allow or deny as rule 1, no matter the source or destination, traffic is either allowed or denied  to everything depending on the first rule. Its happened on a templated firewall and non templated firewall. A simple icmp deny from one host to or denies everything to the internet. Intervlan traffic and site to site traffic is no impacted.

2 Replies 2
Kind of a big deal
Kind of a big deal

Have you tried to reboot the MX ?


Any flow that is already present in the MX flow table won't be subjet to the rule change. A.k.a if you have an active flow , you can delete the rule , place a deny above it and so on and the flow will still work.

Hi Raphael,


rebooted many times! I have reverted back to 16.15 as well, the only change that that has impacted it the intervlan is now blocked. Previously the same scenario was permitting intervlan but denying all internet traffic




As you can see all traffic is hitting a specific rule at no 1

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