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Asus RT-AC66 running on 100% cpu

Discussion in 'ASUS AC Routers & Adapters' started by MoogLe, Jan 11, 2017.

  1. MoogLe

    MoogLe Regular Contributor

    Joined:
    Feb 6, 2012
    Messages:
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    Hey guys,

    We've been having some power outages recently and it has caused my router to really start acting up.

    This is the second time that the router has been running at 100% cpu utilization and I noticed that it pretty much kills the wifi reliablility.

    Last time I had to do a firmware update and factory reset to get it back to normal CPU levels.

    I'm wondering, is there an easier method to kill whatever process is taking up all the cpu cycles?

    I'm running Merlin 380.64_2 and no usb or hard drives attached to the router.
     
  2. MoogLe

    MoogLe Regular Contributor

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    Just tried a factory reset and it didnt seem to even help this time. Was still running at 100% with factory settings....

    Hope you guys can give me some hope that this router isn't fried :(
     
  3. swetoast

    swetoast Senior Member

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    do you have anything from the syslog when it acts up ? or a ps -w from shell even ? would narrow it down whats causing the cpu usage
     
    Nullity likes this.
  4. MoogLe

    MoogLe Regular Contributor

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    I'm affraid I am not so advanced yet.

    I did look at the syslog but can't really decipher anything in there.

    Here's what my syslog has been showing on jan 11th

     
  5. MoogLe

    MoogLe Regular Contributor

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    I turned off my 2.4 ghz antenna and got the cpu down to 75%

    But another wierd issue im having is that when my devices try to connect to my 5ghz network its saying that im using the wrong password, eventhough it's right. If I change the SSID to something else, it will work just fine, when I go back to my default SSID, same problem. I also had this problem yesterday which went away after resetting and rebooting a couple of times but I could not figure out the root issue....
     
  6. Nullity

    Nullity Very Senior Member

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    I'd definitely try running "ps" and/or "top" via SSH/telnet. It'll show you exactly what's causing it.
     
  7. MoogLe

    MoogLe Regular Contributor

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    any links to a guide on how to do that?
     
  8. MoogLe

    MoogLe Regular Contributor

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    ok so nevermind the guide

    Here is what ps gave me


    And Top was showing me a cpu utilization of below 10% most of the time...... with httpd -i br0 usually using the most cpu cycles at around 6-8%

    so..... what now?
     
  9. swetoast

    swetoast Senior Member

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    is your dropbear configured for wan usage ?
     
  10. MoogLe

    MoogLe Regular Contributor

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    I have no idea what dropbear is
     
  11. swetoast

    swetoast Senior Member

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    ssh dropbear

    Administration > System > SSH Daemon

    that should always be off or lan only

    just looking at the log it seems like that one is facing wan
     
  12. MoogLe

    MoogLe Regular Contributor

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    Oh yea

    I actually just turned that on cause i thought it was needed to telnet into the router

    It is currently set to LAN only

    So yea that is definately not the root issue
     
  13. MoogLe

    MoogLe Regular Contributor

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    So i dont get why top is showing such a low cpu utilization and the web interface is showing a very high %.

    Or am i reading the top session % wrong?
     
  14. swetoast

    swetoast Senior Member

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    nope your not reading it wrong, the trick is to catch it when it starts acting up.
     
  15. MoogLe

    MoogLe Regular Contributor

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    Its still showing 75-85% utilization in the web interface. While the ssh session is showing below 10%

    I had them both open at the same time.
     
  16. swetoast

    swetoast Senior Member

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    from my experience the webui lives its own life i trust top and ps rather then the webui
     
  17. MoogLe

    MoogLe Regular Contributor

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    I can understand that

    BUT

    The high utilization on the web interface seems to coincide with the wifi issues.

    Just before the power went out, I just so happen to have opened an app on my phone "Wifi sweetspot" that checks your wifi's performance. I was getting around 300mb/s average. After the outage im hovering around 30 if I can even connect.

    The wired network works fine, no issues at all, it's just the wifi that's all jacked up. I also have an RTN66U working as an access point which also seems to having similar issues.

    Yesterday when I had these same issues, everything seemed to get back to normal once I got the cpu utilization down to around 30%.
     
  18. MoogLe

    MoogLe Regular Contributor

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    So yea,

    Utilization is back down and everything is back to normal.

    I'm stumped on what is causing this....
     
  19. MoogLe

    MoogLe Regular Contributor

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    No ideas?

    This keeps happening everytime the router loses power. Takes a while before it gets back to normal.
     
  20. MoogLe

    MoogLe Regular Contributor

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    I figured it out.

    The culprit turned out to be my Nvidia Shield TV.

    I think what's happening is since the shield is running Plex media server and it gets the media from my NAS, every time I lose power, the shield boots up much faster than my NAS, and it keeps trying to connect to the NAS unsuccessfully. For some reason I have to reboot it to successfully reconnect to the NAS.

    I don't get why this is making my router go absolutely crazy though, how much traffic could this possibly be causing?
     
  21. Reinvented

    Reinvented Occasional Visitor

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    Could be using a lot if your PMS is exposed to the internet for shared streaming, etc.
     

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