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Every day I m running my daily cron backup, I noticed that at the end of the backup procedure my server goes offline for about 2 minutes. This happens every day.

Server details: Intel® Core™ i7-920 Quadcore incl. Hyper-Threading Technology RAM: 12 GB DDR3 RAM Hard discs 2: x 1500 GB SATA-II HDD (Software-RAID 1)

Keep in mind that I only host 40 websites that use only a fraction of the servers resources.

Backup is scheduled early in the morning were traffic is minimum.

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Use the uptime or last commands to see if the server is actually restarting, if its not that may mean that are losing network access.

What way are you checking if your system is offline? Are you trying to SSH in?

Look inside /var/log/messages or /var/log/syslog at the time of the outages to see whats going on. If you can be on SSH during the backup scripts runtime have a running instance of top to see what is going.

Finally what type of backup is this? Offsite using rsync, ftp or something internal? Perhaps posting a copy of the cronjob (sans any personal info) would be usefull

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I m usually working late with on my websites so I noticed one of them going offline and then I tried ssh access which failed. Server is not restarting because uptime is steady(300+ days). – makmour Apr 2 '11 at 4:45
Backup is made from a .pex file provided by my hosting panel, I only setup cron job run time. Cron Job goes like this: cd /xxx/xxxx/bin ; ./backup.pex --domains all --output-dir /xxx/xxxxx/xxxxx/daily --email – makmour Apr 2 '11 at 4:52
/var/log/messages shows only the following that repeats for ever: Apr 2 05:23:01 xxxx clamd[28694]: SelfCheck: Database status OK. Apr 2 05:23:28 xxxx xbt_tracker: Access denied for user 'xxxx'@'localhost' (using password: YES) ..... Apr 2 05:32:58 xxxx last message repeated 4 times Apr 2 05:33:01 xxxx clamd[28694]: SelfCheck: Database status OK. – makmour Apr 2 '11 at 4:53
@makmour: since the internals of the .pex script/binary is unknown, you'll either need to gain insight into the internals (do a 'file backup.pex' to see if it's text/ASCII), or speak directly to the provider of your hosting panel. Perhaps part of the backup restarts networking or something equally obvious. – Zayne S Halsall Apr 2 '11 at 6:50
Hi @Zayne!This is what the pex contains pushd dirname $0 >& /dev/null exec /myhomedir/mypanelname/bin/php -c /myhomedir/mypanelname/etc basename $0 .pex.php "$@" popd >& /dev/null while file backup.pex shows a symbolic link to – makmour Apr 2 '11 at 8:11

I have a feeling that the backup, when transferred off your server, saturates the network connection.

Did you manually change the time when the backup runs? If not, it might even be the case that many jobs run at the same time and together, they saturate the whole network segment in the data center because they all have to pass through the same gateway to reach the storage server. Would be a gross misconfiguration, but is still possible.

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thanks for the reply, until now backup is stored locally, I run daily, weekly and monthly backup in different time each one of them. My server hardware doesnt let me think that my main problem is server load so network issues maybe my problem. Is there a way to check this out? Backup time has been setup by me with 3 hours space between my other backups(weekly and monthly) – makmour Apr 2 '11 at 9:24

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