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Dedicated server (CentOS) Keeps going down - HELP:)

Discussion in 'BlackHat Lounge' started by davids355, Feb 17, 2012.

  1. davids355

    davids355 Jr. VIP Jr. VIP Premium Member

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    Over the past few days my dedicated server keeps going down - I have downloaded logs but I don't really know what I am looking for...

    Basically it seems once or twice a day my website (that runs on the server) just becomes un-contactable, the server is also unavailable from SSH.

    A reboot from hosting panel solves the problem.

    Just wondering if anyone has any ideas where I should be looking?
     
  2. nickk

    nickk BANNED BANNED

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    You will surely have some errors at your apache log
     
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  3. ziplack

    ziplack Senior Member

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    Wich panel are u using?
    Kloxo or WHM? other?
     
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  4. -SICK-

    -SICK- Registered Member

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    Which Web Server do you use?

    For apache, please post your error.log (mostly located in /var/log/apache2/error.log) so we can see whats troubling your server. Please use pastebin or something similiar.

    kind regards,
    SICK
     
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  5. ExtraWinner

    ExtraWinner BANNED BANNED

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    Do you have Firewall installed? If not - then go to: http://configserver.com/cp/csf.html and follow the instructions. White list your own IP and set configuration to highest security. See if this helps. If not then change security setting to lowest protection and sign up for Cloud Flare free account. Try to change nameservers and follow their instructions on setting up DNS.
    Also try to rise connection limit in WHM -> Service Configuration -> Apache Configuration -> Global Configuration -> Go from "Minimum Spare Servers" to "Max Clients" and double all values there.
    If none of those will help - contact your DC and check if they have any issues with their rack/line.
     
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  6. jazzc

    jazzc Moderator Staff Member Moderator Jr. VIP

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    Most of my servers run CentOS. If you want me to take a look via SSH, PM me :)
     
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  7. davids355

    davids355 Jr. VIP Jr. VIP Premium Member

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    I am with 1and1. Have access to Plesk and also 1and1's own control panel.

    Var/log/ does not contain apache folder, nearest thing I have is httpd folder - is that the one?

    Here is my firewall rules:
    [​IMG]

    I have website, email and SSH that I use.
    These are the default rule set that was created by host.

    What is Cloud Flare?

    Also try to rise connection limit in WHM -> Service Configuration -> Apache Configuration -> Global Configuration -> Go from "Minimum Spare Servers" to "Max Clients" and double all values there.
    <--Not sure about this? As I said, I am with 1and1, have access to Plesk or 1and1 control panel (not much settings there).

    Regarding host, have already checked and they dont have any issues their end...
     
  8. ExtraWinner

    ExtraWinner BANNED BANNED

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    Yeah, not sure about Plesk. I used Plesk just once and I ran away from it.
    Cloudflare is DNS manager.
    You do not have management plan with 1and1?
     
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  9. dr.pepper

    dr.pepper Regular Member

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    Disable all email addons you may have - even if you dont use them. Had this many many times. Ask your hosts to clear your email queue
     
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  10. davids355

    davids355 Jr. VIP Jr. VIP Premium Member

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    OK I will take a look at cloudflare thanks:)

    1and1 support are good, but my server is unmanaged root server.

    Dont have any email addons as such, just standard email - accessed via pop - and only like 1 account:)
    I will look up clearing queues.Thanks>
     
  11. davids355

    davids355 Jr. VIP Jr. VIP Premium Member

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    Thanks Jazz. I will action advice I have been given so far. If it goes down again tomorrow, Il shoot you a PM:)
     
  12. messiaah

    messiaah Registered Member

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    if your server is serving high traffic and you are using apache try to install nginx on the server to handle the traffic will reduce the cpu and memory usage
     
  13. davids355

    davids355 Jr. VIP Jr. VIP Premium Member

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    Its not really high traffic - only gets about 300-400 uniques per day.
    Also most of the content is pulled in from another server.

    Having said that, it is only a 4000+ AMD X2, 1GB Ram. Dont know if that should be sufficient?
     
  14. messiaah

    messiaah Registered Member

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    oh well various factors you should check concurrent users at given point of time. and if you have ssh access use command top to monitor the utilization to get a better idea of whats going on at the server in real time.
     
  15. davids355

    davids355 Jr. VIP Jr. VIP Premium Member

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    CPU rarely goes over 2% load that's the funny thing:)
     
  16. dr.pepper

    dr.pepper Regular Member

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    Neither did i on my 8 VPS's running CENTOS that i had, but they were still there emailing after every Cron job (even with option turned off) and after certain other things.
    2 weeks of that turned into a massive 30gb file and using 80% of the CPU

    Cleared the queue and ran sound ever since
     
  17. davids355

    davids355 Jr. VIP Jr. VIP Premium Member

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    See what you mean. How do I check/clear queue?