02 - Configuring MAAS with the CLI

The first step in the config journey is logging in. In the CLI, that's a two-stepper:

stormrider@wintermute:~$ sudo maas apikey --username=admin > api-key-file sudo maas apikey --username=admin > api-key-file

You can make sure you got a valid API key by displaying the contents of api-key-file:

stormrider@wintermute:~$ cat api-key-file XXEjkeeqM:zXb7LkuPY7VxShFNhCFDaD8WnP8gLVL8V64GbSn:tTKdwWV64GbSn:tTKdwW

Note that string isn't an actual API key, just characters I made up. Anyway, I can now login to MAAS – but first, let's try maas –help – there's an important distinction that gets skipped over, causing some grief:

stormrider@wintermute:~$ maas --help usage: maas [-h] COMMAND ... optional arguments: -h, --help show this help message and exit drill down: COMMAND login Log in to a remote API, and remember its description and credentials. logout Log out of a remote API, purging any stored credentials. list List remote APIs that have been logged-in to. refresh Refresh the API descriptions of all profiles. init Initialise MAAS in the specified run mode. config View or change controller configuration. status Status of controller services. migrate Perform migrations on connected database. apikey Used to manage a user's API keys. Shows existing keys unless --generate or --delete is passed. configauth Configure external authentication. createadmin Create a MAAS administrator account. changepassword Change a MAAS user's password. admin Interact with http://192.168.43.251:5240/MAAS/api/2.0/

This is the help you get (a) if you're not logged in, or (b) if you don't type a logged-in username after maas - which is a little annoying to me, but it's just how we do it. What you see above isn't even half of what the MAAS CLI will do, but it's all you get as an unrecognized user.

So now, let's login and try that help again:

stormrider@wintermute:~$ maas login admin http://192.168.43.251:5240/MAAS/api/2.0/ < api-key-file You are now logged in to the MAAS server at http://192.168.43.251:5240/MAAS/api/2.0/ with the profile name 'admin'. For help with the available commands, try: maas admin --help

Now, having done that, I can get a much better idea what the CLI will do:

stormrider@wintermute:~$ maas admin --help usage: maas admin [-h] COMMAND ... Issue commands to the MAAS region controller at http://192.168.43.251:5240/MAAS/api/2.0/. optional arguments: -h, --help show this help message and exit drill down: COMMAND account Manage the current logged-in user. bcache-cache-set Manage bcache cache set on a machine. bcache-cache-sets Manage bcache cache sets on a machine. bcache Manage bcache device on a machine. bcaches Manage bcache devices on a machine. block-device Manage a block device on a machine. block-devices Manage block devices on a machine. boot-resource Manage a boot resource. boot-resources Manage the boot resources. boot-source Manage a boot source. boot-source-selection Manage a boot source selection. boot-source-selections Manage the collection of boot source selections. boot-sources Manage the collection of boot sources. commissioning-script Manage a custom commissioning script. commissioning-scripts Manage custom commissioning scripts. dhcpsnippet Manage an individual DHCP snippet. dhcpsnippets Manage the collection of all DHCP snippets in MAAS. dnsresource Manage dnsresource. dnsresource-record Manage dnsresourcerecord. dnsresource-records Manage DNS resource records (e.g. CNAME, MX, NS, SRV, TXT) dnsresources Manage dnsresources. device Manage an individual device. devices Manage the collection of all the devices in the MAAS. discoveries Query observed discoveries. discovery Read or delete an observed discovery. domain Manage domain. domains Manage domains. events Retrieve filtered node events. fabric Manage fabric. fabrics Manage fabrics. fan-network Manage Fan Network. fan-networks Manage Fan Networks. file Manage a FileStorage object. files Manage the collection of all the files in this MAAS. ipaddresses Manage IP addresses allocated by MAAS. iprange Manage IP range. ipranges Manage IP ranges. interface Manage a node's or device's interface. interfaces Manage interfaces on a node. license-key Manage a license key. license-keys Manage the license keys. maas Manage the MAAS server. machine Manage an individual machine. machines Manage the collection of all the machines in the MAAS. network Manage a network. networks Manage the networks. node Manage an individual Node. node-results Read the collection of commissioning script results. node-script Manage or view a custom script. node-script-result Manage node script results. node-script-results Manage node script results. node-scripts Manage custom scripts. nodes Manage the collection of all the nodes in the MAAS. notification Manage an individual notification. notifications Manage the collection of all the notifications in MAAS. package-repositories Manage the collection of all Package Repositories in MAAS. package-repository Manage an individual package repository. partition Manage partition on a block device. partitions Manage partitions on a block device. pod Manage an individual pod. pods Manage the collection of all the pod in the MAAS. rack-controller Manage an individual rack controller. rack-controllers Manage the collection of all rack controllers in MAAS. raid Manage a specific RAID (Redundant Array of Independent Disks) on a machine. raids Manage all RAIDs (Redundant Array of Independent Disks) on a machine. region-controller Manage an individual region controller. region-controllers Manage the collection of all region controllers in MAAS. resource-pool Manage a resource pool. resource-pools Manage resource pools. sshkey Manage an SSH key. sshkeys Manage the collection of all the SSH keys in this MAAS. sslkey Manage an SSL key. sslkeys Operations on multiple keys. space Manage space. spaces Manage spaces. static-route Manage static route. static-routes Manage static routes. subnet Manage subnet. subnets Manage subnets. tag Tags are properties that can be associated with a Node and serve as criteria for selecting and allocating nodes. tags Manage all tags known to MAAS. user Manage a user account. users Manage the user accounts of this MAAS. version Information about this MAAS instance. virtual-machine Manage individual virtual machines. virtual-machines Manage a collection of virtual machines. vlan Manage a VLAN on a fabric. vlans Manage VLANs on a fabric. vm-host Manage an individual vm-host. vm-hosts Manage the collection of all the vm-hosts in the MAAS. vmfs-datastore Manage VMFS datastore on a machine. vmfs-datastores Manage VMFS datastores on a machine. volume-group Manage volume group on a machine. volume-groups Manage volume groups on a machine. zone Manage a physical zone. zones Manage physical zones. This is a profile. Any commands you issue on this profile will operate on the MAAS region server. The command information you see here comes from the region server's API; it may differ for different profiles. If you believe the API may have changed, use the command's 'refresh' sub-command to fetch the latest version of this help information from the server.

Wowee! Look at all the commands! The very first time I tried to use the MAAS API (before I actually hired on at Canonical), I was using various commands I could find in the documentation that actually returned things I wanted, and then digging it out of the JSON output. Not fun. Then someone reminded me about jq (we'll come to that in a minute), and things got a little easier. Eventually, I asked one of the developers what the deal was, and learned that I just missed a the section called "Get help" in the CLI introduction. After that, a whole new world opened up.

But we came here to configure MAAS, not tell stories, so let me see what I can do with this beast.

The very first blank line you encounter in the MAAS UI is the DNS server IP address. In the UI, I just type "8.8.8.8" (Google's DNS server) and forget about it. But the CLI has no box, so how do I get there? Well, there is a subcommand called <code>dnsresource~, let's see what that does.

stormrider@wintermute:~$ maas admin dnsresource --help Usage: maas admin dnsresource [-h] COMMAND ... Manage dnsresource. optional arguments: -h, --help show this help message and exit drill down: COMMAND read Read a DNS resource update Update a DNS resource delete Delete a DNS resource

Okay, let's be naive and try that:

stormrider@wintermute:~$ maas admin dnsresource read Usage: maas admin dnsresource read [--help] [-d] [-k] id [data [data ...]] Read a DNS resource positional arguments: id data optional arguments: --help, -h Show this help message and exit. -d, --debug Display more information about API responses. -k, --insecure Disable SSL certificate check Read a DNS resource by id. the following arguments are required: id, data

Well, that isn't going to help me, I don't have any idea what the "dnsresource id" would be. Hmmm. Oh, wait. This CLI follows the "collection-instance" rule, that is, listing DNS resources would be part of a collection, so would be pluralized. So, for example, I can read <code>dnsresources~ (plural) and maybe find out something:

stormrider@wintermute:~$ maas admin dnsresources read Success. Machine-readable output follows: []

Well. Maybe I should try the CLI documentation. Looking at the "Quick questions" under common tasks, I see there's one about setting a DNS forwarder. Let me check that out. Hmmm, yeah, that might be what I want. There's a easy way to tell: I can check the DNS setting in the MAAS dashboard in the UI, run the CLI command I found, and see if that sets it.

Okay, actually, I cheated first. I went and asked my friend Lee, who knows how this works, and I kept asking until I annoyed him. But it's useful to illustrate that there was a way to get this from the doc and experimentation, which I should have done. * Sorry, Lee. Owe you lunch. Maybe that's two lunches. *

Hey, in that field, it even says "DNS forwarder" – so let me try it:

stormrider@wintermute:~$ maas admin maas set-config name=upstream_dns value="8.8.8.8" Success. Machine-readable output follows: OK

And it sets it! Woo-hoo, it worked! It wasn't obvious whether I needed to type the IP address with quotes, but I did, and it paid off. I guess I could try it without quotes to see what happens:

stormrider@wintermute:~$ maas admin maas set-config name=upstream_dns value=9.9.9.9 Success. Machine-readable output follows: OK

And that works, too, so I'll change it back real fast before weird things start to happen, since I have no idea what "9.9.9.9" is.

note to self: always RTFM. before annoying my friend Lee.

The next thing would be to import images. When I look at the dashboard, it's already been done, but TBH it was already synched when I logged in and opened the dashboard, so it must be automatic for at least one default image. Dunno. But I can bring in some other image (like Ubuntu 16.04 LTS) just to see how that works, and I can figure out how to confirm that the 18.04 (default) image is actually here.

Well, this time actually consulting the manual, it says I can confirm 18.04 by entering the following command:

stormrider@wintermute:~$ maas admin boot-resources read

The JSON resulting from this command is rather lengthy:

Success. Machine-readable output follows: [ { "id": 7, "type": "Synced", "name": "grub-efi-signed/uefi", "architecture": "amd64/generic", "resource_uri": "/MAAS/api/2.0/boot-resources/7/" }, { "id": 8, "type": "Synced", "name": "grub-efi/uefi", "architecture": "arm64/generic", "resource_uri": "/MAAS/api/2.0/boot-resources/8/" }, { "id": 9, "type": "Synced", "name": "grub-ieee1275/open-firmware", "architecture": "ppc64el/generic", "resource_uri": "/MAAS/api/2.0/boot-resources/9/" }, { "id": 10, "type": "Synced", "name": "pxelinux/pxe", "architecture": "i386/generic", "resource_uri": "/MAAS/api/2.0/boot-resources/10/" }, { "id": 1, "type": "Synced", "name": "ubuntu/bionic", "architecture": "amd64/ga-18.04", "resource_uri": "/MAAS/api/2.0/boot-resources/1/", "subarches": "generic,hwe-p,hwe-q,hwe-r,hwe-s,hwe-t,hwe-u,hwe-v,hwe-w,ga-16.04,ga-16.10,ga-17.04,ga-17.10,ga-18.04" }, { "id": 2, "type": "Synced", "name": "ubuntu/bionic", "architecture": "amd64/ga-18.04-lowlatency", "resource_uri": "/MAAS/api/2.0/boot-resources/2/", "subarches": "generic,hwe-p,hwe-q,hwe-r,hwe-s,hwe-t,hwe-u,hwe-v,hwe-w,ga-16.04,ga-16.10,ga-17.04,ga-17.10,ga-18.04" }, { "id": 3, "type": "Synced", "name": "ubuntu/bionic", "architecture": "amd64/hwe-18.04", "resource_uri": "/MAAS/api/2.0/boot-resources/3/", "subarches": "generic,hwe-p,hwe-q,hwe-r,hwe-s,hwe-t,hwe-u,hwe-v,hwe-w,ga-16.04,ga-16.10,ga-17.04,ga-17.10,ga-18.04" }, { "id": 4, "type": "Synced", "name": "ubuntu/bionic", "architecture": "amd64/hwe-18.04-edge", "resource_uri": "/MAAS/api/2.0/boot-resources/4/", "subarches": "generic,hwe-p,hwe-q,hwe-r,hwe-s,hwe-t,hwe-u,hwe-v,hwe-w,ga-16.04,ga-16.10,ga-17.04,ga-17.10,ga-18.04,hwe-18.10,hwe-19.04" }, { "id": 5, "type": "Synced", "name": "ubuntu/bionic", "architecture": "amd64/hwe-18.04-lowlatency", "resource_uri": "/MAAS/api/2.0/boot-resources/5/", "subarches": "generic,hwe-p,hwe-q,hwe-r,hwe-s,hwe-t,hwe-u,hwe-v,hwe-w,ga-16.04,ga-16.10,ga-17.04,ga-17.10,ga-18.04" }, { "id": 6, "type": "Synced", "name": "ubuntu/bionic", "architecture": "amd64/hwe-18.04-lowlatency-edge", "resource_uri": "/MAAS/api/2.0/boot-resources/6/", "subarches": "generic,hwe-p,hwe-q,hwe-r,hwe-s,hwe-t,hwe-u,hwe-v,hwe-w,ga-16.04,ga-16.10,ga-17.04,ga-17.10,ga-18.04,hwe-18.10,hwe-19.04" } ]

Okay, that's a lot of information, but it looks like I have a bunch of 18.04 images downloaded and synched. Let me try to get a little fancy with a grep and see if I can make that list shorter:

stormrider@wintermute:~$ maas admin boot-resources read | grep architecture

This produces a quick list of the images I've successfully downloaded:

"architecture": "amd64/generic", "architecture": "arm64/generic", "architecture": "ppc64el/generic", "architecture": "i386/generic", "architecture": "amd64/ga-18.04", "architecture": "amd64/ga-18.04-lowlatency", "architecture": "amd64/hwe-18.04", "architecture": "amd64/hwe-18.04-edge", "architecture": "amd64/hwe-18.04-lowlatency", "architecture": "amd64/hwe-18.04-lowlatency-edge",

That definitely confirms 18.04. But what are those three or four on top? Looking at the massive JSON output, I can see that they have names like "open-firmware," "uefi," and "pxe." Okay, so those are images that can PXE-boot machines, basically. But how could I sort this information out in a neat way?

If you're going to use the MAAS CLI – or anything with JSON-based output – you'll want to consider learning the command line tool jq. It's quite handy for parsing the JSON output of the MAAS CLI. So, for example, if I want a (sorta) formatted table of names and architectures, I can run my last command through jq like this:

stormrider@wintermute:~$ maas admin boot-resources read | jq -r '.[] | "\(.name)\t\(.architecture)"'

This gives me a clean image list that looks something like this:

grub-efi-signed/uefi amd64/generic grub-efi/uefi arm64/generic grub-ieee1275/open-firmware ppc64el/generic pxelinux/pxe i386/generic ubuntu/bionic amd64/ga-18.04 ubuntu/bionic amd64/ga-18.04-lowlatency ubuntu/bionic amd64/hwe-18.04 ubuntu/bionic amd64/hwe-18.04-edge ubuntu/bionic amd64/hwe-18.04-lowlatency ubuntu/bionic amd64/hwe-18.04-lowlatency-edge

Okay, I cheated just a little there, too: I cleaned up the tabs a little, which wouldn't be quite as well lined-up unless you have a really wide tab setting (which is possible). Even what I did isn't enough to straighten it out totally, but the output is still readable, anyway.

So you can see that I basically have (a) the images I need to boot machines, and (b) an 18.04 image (set) to deploy. That's a good start, but let me see if I can pull down another image with the CLI. I know I can select images with the boot-source-selections command, so let me try that with "Trusty" (Xenial Xerus, aka 16.04):

stormrider@wintermute:~$ maas admin boot-source-selections create 1 \ > os="ubuntu" release="trusty" arches="amd64" subarches="*" \ > labels="*"

The results look like this:

Success. Machine-readable output follows: { "os": "ubuntu", "release": "trusty", "arches": [ "amd64" ], "subarches": [ "*" ], "labels": [ "*" ], "boot_source_id": 1, "id": 2, "resource_uri": "/MAAS/api/2.0/boot-sources/1/selections/2/" }

And that appeared to work, which is good, because that was a long command to type correctly! Sure enough, if I look back at my "Images" tab in the UI, 14.04 LTS is now "Selected for download." Okay, this CLI seems to be working fairly well, let me just keep going and see if I can get it to download, now.

In reality, downloading them – ahem, I mean "importing" them – is a fairly simple command:

stormrider@wintermute:~$ maas admin boot-resources import Success. Machine-readable output follows: Import of boot resources started

Now when I switch back to the Images screen, I can see that 14.04 LTS is downloading, which is fantastic. I'll just let that download for a while and then move on to enabling DHCP.