Filterdns: host_dns: failed looking up

  • What does this error means? I have full of them into logs, but I cannot figure out where it comes from.

    filterdns: host_dns: failed looking up "": hostname nor servname provided, or not known


  • Rebel Alliance Developer Netgate

    It means you are using that hostname in an alias or IPsec endpoint, and it cannot be properly resolved by your DNS server.

    Indeed that hostname does not have a valid record. It comes back empty.

    $ ping
    ping: cannot resolve No address associated with name
    $ host
    $ host -t mx   has no MX record

    So wherever you have that hostname, it isn't valid to use, since it must return an IP address to be used in firewall rules.

  • Yes, I understand that. But what I cannot figure out is where those hostnames are registred in pfSense. I though it was in Captive Portal Allowed Hostnames, but I removed all invalid hostnames, and I still get those errors in the logs.


  • Rebel Alliance Developer Netgate

    It can be anywhere a hostname is allowed: firewall aliases, IPsec endpoints, captive portal allowed hostnames, etc.

    It might be easier to download a copy of the config.xml (From Diagnostics > Command) and then search through the file to see where it is.