[USG FLEX H] Allow DDNS Check Period lower than 5 minutes (e.g. 1 minute)

Options
Zyxel_Judy
Zyxel_Judy Posts: 2,789
Zyxel Certified Network Engineer Level 2 - Nebula Zyxel Certified Network Engineer Level 2 - Switch Zyxel Certified Network Engineer Level 2 - Security Zyxel Certified Network Engineer Level 1 - Nebula
image  Zyxel Employee
edited October 5 in Security Ideas

On USG FLEX H, the DDNS "Check Period" currently has a fixed minimum of 5 minutes. This means that in the worst case, after a WAN IP change, it can take up to 5 minutes before the device even notices and starts the DDNS update — which matters for anyone relying on DDNS for remote access, VPN, or similar services.

This was originally raised by @Maverick87 here: USG FLEX H – DDNS public IP, decrease minimum check period

Proposed idea:
Lower the minimum Check Period to 1 minute. Most DDNS providers cap their DNS record TTL around 60 seconds, so going below 1 minute is unlikely to bring much additional benefit on the DNS resolution side — but going from 5 minutes down to 1 minute would meaningfully cut the worst-case detection delay.

If you'd find this useful too, feel free to vote/comment below so we can gauge interest.

Zyxel_Judy

4
Up Down
4 votes

Active · Last Updated

Comments

  • Maverick87
    Maverick87 Posts: 490
    Zyxel Certified Network Administrator - WLAN Zyxel Certified Network Administrator - Nebula Zyxel Certified Network Administrator - Security Zyxel Certified Sales Associate
    image  Master Member
    Options

    In my opinion decrease to seconds it's only for "observe" if the IP is changed, not for update "as-is".

    For example: if I set "10 seconds" into the field; every 10 seconds I check the URL page that return to me the external IP. Then, I compare this returned IP with the external effective IP; if is not changed do nothing, if is changed, update the DDNS.

    The field is only to trigger a check, not for update really. Presumibly I can would check the change every 10 seconds, but can be possible that the effective external IP never change or change 1-2 per day.

  • PeterUK
    PeterUK Posts: 4,796
    250 Answers 2500 Comments Friend Collector Ninth Anniversary
    image  Guru Member
    edited October 6
    Options

    Just in case it help the case of lowering Check Period the Public IP option only the DDNS part only executes only if like the check at say http://ip1.dynupdate.no-ip.com/ IP is new to what is stored to then do DDNS update.

  • Maverick87
    Maverick87 Posts: 490
    Zyxel Certified Network Administrator - WLAN Zyxel Certified Network Administrator - Nebula Zyxel Certified Network Administrator - Security Zyxel Certified Sales Associate
    image  Master Member
    edited October 6
    Options

    Exactly, so it might make sense to run a check every n seconds and then perform the DDNS update only if the current IP differs from the previous one.

    For this very reason, I opened a support ticket regarding the FWA515 to see if it is possible to perform IP checks "in-house"; this way, I avoid external "flooding" and keep everything local.

    https://community.zyxel.com/en/discussion/34178/fwa515-public-private-url-for-return-the-wan-external-ip

Categories

Security Help Center

EnglishTiếng ViệtРусскийไทย中文（台灣）