The visual diagrams still confuse me after so many years and I always forget…so here it is: INNER JOIN gets all records from one table that have some related entry in a second table LEFT JOIN gets all records from the LEFT linked table but if you have selected some columns from the RIGHT table, […]
If /etc/fstab is correct, you can simply type: # mount -n -o remount / If /etc/fstab is wrong, you must give the device name and possibly the type, too: e.g. # mount -n -o remount -t ext4 /dev/sda3 /
Monitor the status: crm_mon Migrate all resources to another node: crm resource migrate rg_main <fqdn_node_name> Take node offline and online (be careful, this sets a ‘prefer’ to the other node to force a transition, which may or may not get removed afterwards): crm node standby crm node online Start and stop all resources (warning, this […]
Enable mail relaying from a specific IP or range of IPs. 1. Exchange Management Console -> Server Configuration -> Hub Transport 2. New Receive Connector * Set remote network to the IP or range you want to allow relay from (default is any IP so watch out here) * “Externally Secured” authentication * “Exchange Servers” […]
If a (poorly coded) app reaches the maximum number of files or folders per directory in Linux, you may see errors like this: Error happened when generating Download Link. Please try again or Contact administrator. (ERROR:mkdir) A quick and dirty way to increase the limit (and overall performance of the system) is to add the […]
This will set the ‘ADMIN’ user password back to default of ‘ADMIN’. You could set it to anything you want, this is just an example. yum -y install ipmitool modprobe ipmi_devintf ipmitool -I open user set password 2 ADMIN
Don’t try to reinvent a complex and highly refined wheel, especially when customer data is involved. Please use phpass on any PHP project. (that’s PH-Pass) http://www.openwall.com/phpass/ Good reading for password hashing in general. http://www.openwall.com/articles/PHP-Users-Passwords
wget http://layer1.rack911.com/before_apache_make -O /scripts/before_apache_make chmod 700 /scripts/before_apache_make ## Rebuild apache (might want to do it thru WHM instead) /scripts/easyapache –build
I’ve got a couple of Linux machines that are sitting outside of the Sflow ‘zone’ and AS traffic stats go unmeasured. I wanted to get a rough idea on the number of connections per AS number so here’s a little app that parses netstat and sorts AS numbers by number of connection. NOTE1: This won’t […]
There are 3 primary options: 1. Use PAR with PAR::Filter::Obfuscate or PAR::Filter::Crypto 2. Use Filter::Crypto::CryptFile (requires certain modules installed on target system) 3. Encrypt modules with Module::Crypt.