Add outbound MX record SPF

Solution: Add a TXT record for your domain
@ v=spf1 mx ip4:mail.host.com ~all

Issue: Somehow external mailservers need to validate the server it received mail from is legitimate. This apparently is not always an issue, but I figured I would set this up correctly, regardless.

In the past we would simply add an MX record with the highest priority (even if the server was simply an outbound server). This really is not a great approach. The SPF (TXT) record of type MX is the right way to accomplish this.

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P2V using dd for KVM-QEMU guest

Preface: I have certainly not exhaustively tested this process. I had a specific need and found a specific solution that worked. Situation: I was issued a shiny new laptop running Red Hat Enterprise Linux 7 (with Corp VPN, certs, Authentication configuration, etc...) The image was great, but I needed more flexibility on my bare metal. So, my goal was to P2V the corporate image so I could just run it as a VM. * Remove corporate drive and install new SSD * install corp drive in external USB-3 case * Install RHEL 7 on new SSD * dd old drive to a disk-image file in a temp location which will be an image which is the same size as your actual drive (unless you have enough space in your destination to contain a temp and converted image) * convert the raw disk-image to a qcow file while pushing it to the final location - this step should reduce the disk size - however, I believe it will only reduce/collapse zero-byte blocks (not just free space - i.e. if you de...

Extending SNMP to run arbitrary shell script

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RHN Satellite Server (spacewalk) repomd.xml not found

"repomd.xml not found" If you add a channel, or if your RHN cache gets corrupted, and one of your guests complains that it cannot find repomd.xml for jb-ews-2-x86_64-server-5-rpm (for example) - you need to rebuild your repodata cache. Normally this is an automated job - which is exemplified by the fact that you have obviously built out your entire Satellite environment and never had to do any of the steps you are about to do. So - some prep work: Open 3 terminals to your Satellite Server and run: # Term 1 cd /var/cache/rhn watch "ls -l | wc -l" # Term 2 pwd cd /var/log/rhn tail -f rhn_taskomatic_daemon.log # Term 3 satellite-sync --channel=jb-ews-2-x86_64-server-5-rpm Once the satellite-sync has completed, you >should< see the count increment by one. If you are unlucky (like me) you will not. You then need to login to the Satellite WebUI as the satellite admin user. Click on the Admin tab (at the top) Task Schedules (on the left) fin...

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