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RT-AC86U 384.5 and 384.6 alpha2 Router Powers Down/No Lights, No Access

Discussion in 'Asuswrt-Merlin' started by GHammer, Jul 8, 2018.

  1. GHammer

    GHammer Regular Contributor

    Joined:
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    I have an odd issue.
    I have had two different RT-AC86U simply shutdown at nearly the same time of day.
    I sent the first router back thinking it was a bad router. The second one running 384.5 then 384.6 alpha2 did the same.
    I was away for 10 days and on the 2nd day, no access to my home server. When I returned the router was dark with no connectivity for any device. Had to power cycle the router. I factory reset the router and loaded alpha2. Today (2 days later) I awoke to find a dark router again. Hit the power button and it powered up and was functioning fine.
    My router is on a UPS with around 6 hours of runtime, so no power failure. Other devices connected to the UPS show no loss of power.

    Each time the system logs show nothing of concern until the time of the failure.
    Code:
    Jul  8 05:52:02 kernel: Emergency Sync complete
    Again, two routers, two different builds, same failure at the same time of day (05:50-05:52)

    I have reset the router and returned to the current ASUS firmware for now.

    The only thing different in the config of the router is DHCP assignments, enabling IPV6, and establishing port forwarding for a server.

    I saved the full system log for the last failure if interested.
     
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  3. NoSync

    NoSync Occasional Visitor

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    On my RT-AC86U I sometimes get that if I reboot from the UI or change wireless settings (no matter the fw version). Never had it happening spontaneously though.
     
  4. ColinTaylor

    ColinTaylor Part of the Furniture

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    Do you have an automatic reboot scheduled for 05:50 (Administration > System)?
     
  5. GHammer

    GHammer Regular Contributor

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    No, I do have one, but it is 06:02
     
  6. ColinTaylor

    ColinTaylor Part of the Furniture

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    That's too close to be a coincidence. Try disabling the reboot and see if the problem goes away.
     
  7. GHammer

    GHammer Regular Contributor

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    That would suggest the router is looking ahead.
    It's a daily reboot, so why only certain days? It didn't fail for the first one or two days.

    I will see if the router does the same with the stock ASUS firmware.
    I put it in place before folks are up and about, so don't want to wipe the router and reconfig from factory settings to get back to RMerlin during the day.

    If it is dying because of looking ahead on the scheduled restart, that would be fixable.
     
  8. ColinTaylor

    ColinTaylor Part of the Furniture

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  9. GHammer

    GHammer Regular Contributor

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    Indeed we have. Then, I returned that router for refund and bought another finding the same issue.
     
  10. john9527

    john9527 Part of the Furniture

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    What is your 'default' time when the router first boots before the clock is sync'd?
     
  11. GHammer

    GHammer Regular Contributor

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    May 5 01:05:05
     
  12. GHammer

    GHammer Regular Contributor

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    Makes sense that a scheduled restart could be the culprit here.

    I have reset to factory, loaded alpha2, formatted jffs, reset to factory, reconfigured manually.
    No scheduled restarts.
    Plain vanilla save for DHCP assignments, enabling IPV6, and establishing 2 port forwarding rules.
    Let's see where this takes us.
     
  13. GHammer

    GHammer Regular Contributor

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    It seems there is interaction between scheduled restarts and the router simply turning off.
    I disabled the scheduled restarts and enough time has passed for the issue to appear.
    Still running with no problems to report.

    This time I did not enable full cone NAT. Last try it was enabled. When enabled, there were errors shown in the logs. No torrents, etc that would cause high connection rates. With the full cone off, no error.
    nf_conntrack: expectation table full
    net_ratelimit: 15 callbacks suppressed

    We can live with the lack of full cone and without the scheduled restarts.
     
  14. RMerlin

    RMerlin Super Moderator

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    You can increase it, using a nat-start or firewall-start script.

    http://netfilter.vger.kernel.narkive.com/8eUaStlj/expectation-table-size
     
  15. GHammer

    GHammer Regular Contributor

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  16. Treadler

    Treadler Regular Contributor

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    Using either scheduled wireless, or scheduled reboot, results in intermittent power downs for me.
    IMHO, scheduling is ‘broken’, & I no longer bother using it/them.
     
    GHammer likes this.
  17. GHammer

    GHammer Regular Contributor

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    I guess the scheduler needs a little love then.
     
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