Using RHEL6 to share RAID volume via iSCSI: the Mystery of the Missing LUN

My use case was pretty simple. I wanted to share out a raw device via iSCSI to a nearby host on the 172.16.2.x network.

In addition to a minimal Red Hat Enterprise Linux 6 (or equivalent) install, a few packages are needed:

# yum install -y iscsi-initiator-utils scsi-target-utils sg3_utils lsof

I knew the device I wanted to share was /dev/sdb by looking at the output from dmesg:

RHEV 3.0 Firewall Annotated iptables Configuration for Netfilter

When Red Hat Enterprise Virtualization Manager for Servers is installed, it offers to configure iptables for you:

Firewall ports need to be opened.
You can let the installer configure iptables automatically overriding the current configuration. The old configuration will be backed up.
Alternately you can configure the firewall later using an example iptables file found under /usr/share/rhevm/conf/iptables.example

Here's an annotated version of what the RHEVM installer will give you:


Why Your KVM Network Bridge Isn't Working

You're trying to get libvirt and KVM working on Red Hat Enterprise Linux 6 or CentOS 6, or maybe even Scientific Linux 6. But it's not going well.

You wanted your VMs to have full access to the network and you've discovered that virbr0 doesn't do that. Finally you stumbled upon the way to do it by Creating a Network Bridge using your primary interface. And yet, something just ain't right.


Solved: Renaming em1 to eth0 on Red Hat Enterprise Linux 6

We had a software package that had a braindead licensing scheme. To generate the license, it uses the MAC address of the network interface card of the machine you are running it on. OK, that's a way of identifying a unique machine. But here's the kicker. It just assumes that your ethernet device is /dev/eth0.

For a while now, NICs that are embedded on the motherboard are identified by udev as em1, em2, etc. This is part of an attempt to make interface naming more predictable and meaningful.



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