Now that our 389ds instance is fully configured and ready to go, let’s have a look at how to back it up and potentially restore it if a disaster occurs.
In part 3 we’ve looked at ACLs and how to use them to restrict privileges of directory users. Unfortunately it’s still possible to access the 389 Directory Server instance that we’ve created all the way back in part 1 anonymously (i.e. without authenticating as a directory user) which renders the ACLs somewhat pointless. So it’s time to tighten up security… Read more »
Now that we’ve set up an instance of the 389 Directory Server in part 1 and configured essential plugins in part 2, it’s time to take a closer look at access-control list (ACLs). After all, regular users of the directory shouldn’t be able to change data that they’re not supposed to or have universal read access in most use cases.
In part 1 we’ve looked at how to install 389 Directory Server and create an instance. While this left us with a fully working LDAP server there are some plugins that greatly increase quality of life and might even be considered essential.
The Lightweight Directory Access Protocol or LDAP for short has been around for quite a while. While more modern technologies like OpenID, OAuth or SAML are often used for authentication and authorisation purposes when it comes to applications, APIs etc. on the internet these days, LDAP is still widely used for various use cases. For same-sign on purposes it is… Read more »
On Linux qemu-nbd can be used to access disk images in different formats as if they were block devices. For example, to mount a VHD file run To unmount and disconnect the nbd device run
Currently the Fedora projects provides cloud images as qcow2 and raw disk files. Microsoft’s Azure however only supports VHD files. Fortunately qemu-img can convert between those formats: Note that the subformat options fixed and force_size are required for Azure to be able to use the disk image since Azure only supports fixed sized disks.
Migrating a virtual machine from one host to another is usually no big deal if both hosts run the same VMM. But what if one wants to move a VM from a host running a different hypervisor than the target host? In the case of moving a VM from KVM to ESXi that’s just not (easily) possible. However, one can… Read more »
Create a new image file (10GiB): (Note: You can also create a sparse file with dd’s seek option. Have a look at the dd manpage or the examples on http://en.wikipedia.org/wiki/Dd_(Unix)) Create the new filesystem: Label the filesystem: Edit the DomU’s config file, /etc/xen/<hostname>.cfg and add the new disk: Start the VM: Edit DomU’s /etc/fstab & mount the disk:
Just a little memory hook: When a Xen DomU hangs at “Checking for hardware changes”, it is probably due to a dead xenconsoled process on the Dom0. This happens from time to time but should immediately fix the hanging DomUs.