Tag: CentOS

Relay Mail To Two or Multiple eMail SMTP Servers Simultaneously Using exim in Linux CentOS 6 RHEL 6

Hey there fellow Hurston students! I recently completed migrating a Windows email server running SmarterMail to a Linux server running Zimbra. One of the methods used to ensure a smoother transition over to the Zimbra system was to configure an exim mail relay to receive mail destined for my domains and deliver them to both… Continue reading Relay Mail To Two or Multiple eMail SMTP Servers Simultaneously Using exim in Linux CentOS 6 RHEL 6

IP Address Active/Passive Failover Setup in Linux CentOS 6 RHEL 6 using keepalived

Hey everyone out there in BBS land.  Your old friend Max here to dump out some knowledge on you. Imagine you’re living in a world of two systems and three IP addresses.  One of the IP addresses is really importing and if the system it’s running on explodes, you want it to come back up… Continue reading IP Address Active/Passive Failover Setup in Linux CentOS 6 RHEL 6 using keepalived

Incron, Watcher Python PyInotify Alternative. Recursively Watch A File System for Change Events using inotifywait, inotify

If you have a folder in your home directory called “/root/FilestoWatch” and in there you have a bunch of files and folders that you want to constantly be checked for changes. There are a few options out there for this type of thing: – crond (limited to every minute) – incrond (cannot recursively watch a… Continue reading Incron, Watcher Python PyInotify Alternative. Recursively Watch A File System for Change Events using inotifywait, inotify

How To Setup MySQL Enterprise Monitoring with Zabbix

This article is NOT about how to setup the application called MySQL Enterprise Monitor but rather how to setup MySQL monitoring in your Zabbix Enterprise Monitoring software. Here’s how this works: – Network communication to the server provided by the Zabbix Agent. – Agent side UserParameter settings allow for needed commands to be run against… Continue reading How To Setup MySQL Enterprise Monitoring with Zabbix

Set Default Directory Permissions in Using ACLs

I’ve only tested this on RHEL/CentOS/Scientific Linux but should work on any system running Linux acl. ACL’s are useful for providing more granular file and directory access permissions as a supplement to the standard Unix user/group permissions. Let’s say you want the user ‘funboy’ to have full control over the /disco directory on your system, and… Continue reading Set Default Directory Permissions in Using ACLs

Dell OpenManage System Administrator Startup Error – DSM SA Shared Services cannot start on an unsupported system

OK so what if you’re using CentOS on some Dell hardware and you’ve installed Dell OpenManage System Administrator (OMSA).  You might receive the following error when you try to start it up! Starting Systems Management Data Engine: Failed to start because system is not supported dsm_om_shrsvc: DSM SA Shared Services cannot start on an unsupported… Continue reading Dell OpenManage System Administrator Startup Error – DSM SA Shared Services cannot start on an unsupported system

Show Some Line Numbers in vim (vi) in RHEL/CentOS/Scientific Linux

Alright check this shit out..  I’m one of those dudes who likes to have my text editors display the line number at all times.  CALL ME OLD FASHIONED! So if you want line numbers to be displayed in vi (which is really vim these days in the GNU/Linux version we’re talking about), run the following:… Continue reading Show Some Line Numbers in vim (vi) in RHEL/CentOS/Scientific Linux

How to Install Zabbix Server 2.0 on CentOS 6 or CentOS 5

So you probably know this already but RHEL and CentOS are basically the same, as in they have full binary compatibility.  Here’s how you can install a Zabbix Monitoring Server on CentOS 5 or 6 (AKA RHEL 5 or 6). As well as installing the zabbix client side packages. FIRST!  Setup the yum repo that… Continue reading How to Install Zabbix Server 2.0 on CentOS 6 or CentOS 5