Protect your servers against brute force SSH attacks

February 8, 2013  |  linux, security  |  1 Comment

I bet if any of you have an exposed server to an internet connection, without properly firewall protection, that your server is under heavy fire from hackers around the "world"... By the world I mean mostly China and Russia ssh attacks. If you're curious, on Linux you can check the...

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Installing NGINX on RHEL 5/6 (Centos and Oracle Linux too)

May 14, 2012  |  cloud, linux, security  |  No Comments

I'm an huge NGINX fan. Nginx pronounced “Engine-X” is an open source Web server and a reverse proxy server for HTTP, SMTP, POP3 and IMAP protocols, with a strong focus on high concurrency, performance and low memory usage. Nginx is awesome... really. I use it since 0.6 beta and never had...

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Enterprise Manager (EM) not running after OS timezone change (nmectl_validateTZRegion)

November 12, 2011  |  dba, linux  |  1 Comment

I've installed Oracle Database 11gr2 Oracle_Home ( on an Oracle Linux EC2 instance and then moved that home to a new server. Database was running, listener too, but Enterprise Manager crashed after login and the log file shows that there a problem with the agent timezone: cat /u01/app/oracle/product/11.2.0/dbhome_1/myhost.com_apex/sysman/log/emdctl.trc 2011-11-12 11:03:11,376 Thread-1708107488 ERROR...

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Multiple hanging processes or errors running /etc/cron.daily/rpm

June 27, 2011  |  linux  |  No Comments

If you attempt to run an RPM command  and receive an error message that the RPM database is in use, or if you have multiple zombie cron processes probably you'll need to rebuild the rpm database. Take a look: [root@db2 root]# ps -ef  root     31366 31019  0 04:02 ?      ...

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Oracle database available as a service on Amazon AWS (RDS)

May 24, 2011  |  cloud, dba, linux  |  2 Comments

Today Amazon announced the availability of Amazon RDS for Oracle Database. Now you will be able to run multiple editions of Oracle Database 11g (Release 2) via Amazon RDS. With Amazon RDS, you can provision a pre-configured Oracle database and scale the underlying hardware anytime you want in a couple...

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Oracle Linux 6 does not boot after install! Blank screen…

April 28, 2011  |  linux  |  No Comments

Today I installed Oracle Linux 6 on a Fujitsu Primergy blade, but didn't boot. After sucessfull first part install I've reboot to first boot. In the GRUB menu, I've choose the first option kernel (UEK - Unbreakable Enterprise Kernel). Well, something suddently went wrong. The server did not boot and...

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