≡ Menu

Security

OpenBSD: Configure Network Interface As A Bridge / Network Switch

I have Soekris single board communication embedded computers which is optimized for low power and network usage. The server has four Ethernet ports. How do I setup IPv4 software bridge using OpenBSD operating systems so that the rest of four ports act as a network switch?
[click to continue…]

Sysadmin because even developers need heroes!!!

Ubuntu Linux: Disable Apparmor For Specific Profile / Service Such As Mysqld Server

AppArmor last updated November 9, 2012

How do I use tar and rsync command that can preserve the ACLs, extended attributes and SELinux contexts under CentOS / RHEL / Fedora Linux server while making backups?
[click to continue…]

Linux / UNIX: Encrypt Backup Tape Using Tar & OpenSSL

How do I make sure only authorized person access my backups stored on the tape drives (DAT, DLT, LTO-4 etc) under Linux or UNIX operating systems? How do I backup /array22/vol4/home/ to /dev/rmt/5mn or /dev/st0 in encrypted mode?
[click to continue…]

Nginx Block And Deny IP Address OR Network Subnets

How do I block or deny access based on the host name or IP address of the client visiting website under nginx web server?
[click to continue…]

Linux Default Services Which Are Enabled at Boot

Can you provide a guidance on default CentOS / Fedora / RHEL / Redhat enterprise Linux services which are enabled at boot time by a default? Can you provide set of recommendations for all default services and which to keep for performance and security and which to turn off?
[click to continue…]

CentOS / Redhat: Turn On SELinux Protection

SELinux enforces the idea that programs should be limited in what files they can access and what actions they can take. However, by default it is turned off under RHEL / CentOS 5.x server? How do I turn it on? How can I enable SELinux on CentOS / RHEL 6 IBM server?
[click to continue…]

Linux: Create /tmp And Mount as Partition File With the noexec, nosuid, And nodev

How do I mount /tmp as a separate filesystem (/root/images/tmpfile.bin) with the noexec,nosuid, nodev options under Linux like operating systems?
[click to continue…]

Mac OS X Disable Unnecessary Services

How do I disable unnecessary services under Mac OS X to secure my Mac OS X based desktop / server / laptop?
[click to continue…]

I‘ve brand new Ubuntu Linux server (Apache + PHP5 FastCGI + Lighttpd image only server) installed for my wordpress, mediawiki and vBullietin software. I can load forntpage of all software but user cannot edit any wiki pages or post anything and I get the following error in log file:

PHP Fatal error: Allowed Memory Size of 20971520 Bytes exhausted (tried to allocate 131072 bytes) in /usr/share/mediawiki/includes/OutputHandler.php on line 81

How do I fix this problem?
[click to continue…]