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Sequestering E-Mail

When testing applications one of the concerns is always that their actions don't effect the real-world. One aspect of that this is sending e-mail; the last thing you want is the application you are testing to send a paid-in-full customer a flurry of e-mails that he owes you a zillion dollars. A simple, and reliable, method to avoid this is to adjust the Postfix server on the host used for testing to bury all mail in a shared folder. This way:

LDAP extensibleMatch

One of the beauties of LDAP is how simply it lets the user or application perform searching. The various attribute types hint how to intelligently perform searches such as case sensitivity with strings, whether dashes should be treated as relevant characters in the case of phone numbers, etc... However, there are circumstances when you need to override this intelligence and make your search more or less strict. For example: in the case of case sensitivity of a string. That is the purpose of the extensibleMatch.

Look at this bit of schema:

Android, SD cards, and exfat

I needed to prepare some SD cards for deployment to Android phones. After formatting the first SD card in a phone I moved it to my laptop and was met with the "Error mounting... unknown filesystem type exfat" error. That was somewhat startling as GVFS gracefully handles almost anything you throw at it. Following this I dropped down to the CLI to inspect how the SD card was formatted.

KDC reply did not match expectations while getting initial credentials

Occasionally one gets reminded of something old.

[root@NAS04256 ~]# kinit adam@example.com
Password for adam@Example.Com: 
kinit: KDC reply did not match expectations while getting initial credentials

Huh.

[root@NAS04256 ~]# kinit adam@EXAMPLE.COM
Password for adam@EXAMPLE.COM:
[root@NAS04256 ~]# 

In some cases the case of the realm name matters.

Renaming the Volume Group Containing /

Almost every server I work with is a virtual machine; accordingly I like to do one small install with all the packages that I always want [like pam-nss-ldapd, snmp-utils, dstat, etc...] but don't install by default. Then I make sure VMware tools is installed and operational. From that point forward I can just clone that one VM and add to it when I want a new instance of something.

Private Networks and Bind 9.9.0+

As of BIND 9.9.0 bind is now compliant with RFC6303. RFC6303 addresses the issue that everywhere on the Internet private networks are leaking [People - you need egress firewalls..., egress firewalls, not just ingress]. Name servers receive many queries for addresses that are 'private' [see RFC1918].

Installation & Initialization of PostGIS

Distribution: CentOS 6.x / RHEL 6.x

If you already have a current version of PostgreSQL server installed on your server from the PGDG repository you should skip these first two steps.

XFS, inodes, & imaxpct

Attempting to create a file on a large XFS filesystem - and it fails with an exception indicating insufficient space! There is available blocks - df says so. HUh? While, unlike traditional UNIX filesystems, XFS doesn't suffer from the boring old issue of "inode exhaustion" it does have inode limits - based on a percentage of the filesystem size.

The source files could not be found.

I have several Windows 2012 VMs in a cloud environment and discovered I am unable to install certain roles / features. Attempting to do so fails with an "The source files could not be found." error. This somewhat misleading messages indicates Windows is looking for the OS install media. Most of the solutions on the Interwebz for working around this error describe how to set the server with an alternate path to the install media ...

Playing With Drive Images

I purchased a copy of Windows 10 on a USB thumbdrive. I chose to have media to have (a) a backup and (b) not to have to bother with downloading a massive image. Primarily this copy of Windows will be used in VirtualBox for testing, using Power Shell, and other tedious system administrivia. First thing when it arrived is I used dd to make a full image of thumbdrive so I could tuck it away in a safe place.

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