MAAS Internal URLs


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Introduction

There are a number of internal URLs MAAS uses during commissioning and deployment which are useful to access when debugging. This document describes what they are and how to access them.

Static files

All bootloaders, images, kernels, and initrds found in /var/lib/maas/boot-resources/current on the rack controller are available over both HTTP and TFTP. Directory listing is enabled over HTTP

http://$RACK:5248/images/
tftp://$RACK/

Bootloader configuration files

All bootloader configuration files are available over TFTP and are generated dynamically by the rack controller. The default configuration is used during enlistment. For any other state the MAC address must be included in the request.

PXELinux i386, AMD64

tftp://$RACK/pxelinux.cfg/default
# MAC is delaminated with a '-' e.g 52-54-00-20-b1-01
tftp://$RACK/pxelinux.cfg/01-$MAC

GRUB UEFI AMD64, ARM64

tftp://$RACK/grub/grub.cfg-default-amd64
# MAC is delaminated with a ':' e.g 52:54:00:dd:d1:50
tftp://$RACK/grub/grub.cfg-$MAC

PowerNV/PPC64EL

tftp://$RACK/ppc64el/pxelinux.cfg/default
# MAC is delaminated with a '-' e.g 52-54-00-20-b1-01
tftp://$RACK/ppc64el/pxelinux.cfg/01-$MAC

s390x

tftp://$RACK/s390x/default
# MAC is delaminated with a '-' e.g 52-54-00-20-b1-01
tftp://$RACK/s390x/01-$MAC

Metadata server

MAAS implements a subset of the EC2 metadata service to provide machines with data such as hostname, SSH keys, and user data to be run. Only a subset of data can be accessed anonymously, most data requires OAUTH1 credentials.

Accessing the metadata server

As of MAAS 2.5 each rack controller runs an nginx HTTP proxy service which allows machines to only have to interact with the rack controller.

Metadata directly from the region

http://$REGION:5240/MAAS/metadata/latest/

Metadata through the nginx proxy

http://$RACK:5248/MAAS/metadata/latest

Preseeds

The preseed contains the initial configuration for cloud-init to configure the system. Two URLs are available, one during enlistment and another used by all other environments.

http://$REGION:5240/MAAS/metadata/latest/enlist-preseed/?op=get_enlist_preseed
http://$REGION:5240/MAAS/metadata/latest/by-id/$SYSTEM_ID/?op=get_preseed

Userdata

The userdata contains scripts and other configuration data which is run by cloud-init. MAAS creates userdata by starting with a template and adding additional required data. These templates can be found in

/etc/maas/preseeds/*userdata*

The data is then base64 encoded and returned to the client.

Enlistment userdata

Enlistment userdata can be access anonymously

http://$REGION:5240/MAAS/metadata/enlist/latest/user-data

Userdata for all other ephemeral environments

This method requires OAUTH1 credentials

http://$REGION:5240/MAAS/metadata/latest/user-data