IPAM

Example configuration

The following kind of configuration file needs to be exported in the variable OSS_PARAMS_FILENAME.

        "LO": {
            "V4": {"containers": [], "networks": ["10.255.255.32/32", "10.255.255.0/28", "10.255.255.16/28"], "mask": 0},
            "V6": {"containers": [], "networks": ["dead:beef::/80", "dead:beef:0:1::/80"], "mask": 0},
            "domain_name": ".gso"
        },
        "TRUNK": {
            "V4": {"containers": ["10.255.255.0/24", "10.255.254.0/24"], "networks": [], "mask": 31},
            "V6": {"containers": ["dead:beef::/64", "dead:beee::/64"], "networks": [], "mask": 126},
            "domain_name": ".gso"
        },

Either a non-empty list of networks or a non-empty list of containers is required in the params file per service type. Having both is redundant, but in that case containers take precedence. The mask parameter is irrelevant if the service type uses networks instead of containers.

Host/network allocation

Hosts can be allocated through ipam.new_service_host() resulting in a host record (IPv4, IPv6, A, AAAA) and zero or more CNAME records. This function can be called by passing domain name, hostname, and service type (mandatory). Optinally, you can pass either ipv4/ipv6 addresses, ipv4/ipv6 networks, or nothing. Passing nothing is considered default. In that case:

• If the service type has any container specified in the params file, networks have to be allocated before allocating hosts (through ipam.new_service_networks()). The mask parameter is used to create the new networks. Containers are filled up in the order that they appear in the params file.
• If the service type has any network specified in the params file, those networks are used directly to allocate hosts. Networks are filled up in the order that they appear in the params file.

If you pass addresses or networks, the module will always attempt to use those, but will fail if they don't match the configuration in the params file for the service type (that is, if you request an address or network that places outside of the configured containers/networks).

Networks and hosts can be allocated with extendable attributes. Networks can be created with a comment. CNAME records can be optionally created.

Host/network deletion

The code checks that the resource you are trying to delete is allocated (in terms of IP address space) to the service through containers or networks in the service's configuration. If not, you aren't allowed to delete it.

No host or CNAME records are deleted via the delete_service_host() function until all passed arguments match the hostname, IP, and CNAME data of the host. If anything doesn't match, no record is deleted.

Usage examples

Host/network allocation

The following is a sample call flow to allocate two loopback interfaces and a trunk service. It assumes the Example configuration from the above section is used, where TRUNK has configured containers, and LO has configured networks.

In this example:

• Host hA for service LO uses specific ipv4/ipv6 address pair.
• Host hB for service LO uses nothing (just the service type).
• Host hA for service TRUNK uses a specific ipv4/ipv6 address pair.
• Host hB for service TRUNK uses the ipv4/ipv6 network pair.

Because TRUNK has configured containers rather than networks, new_service_networks() must be called first to create a network for the hA-hB TRUNK. This isn't needed for LO, which automatically uses the first configured network with available space to allocate new hosts.

    hostname_A = 'hA'
    hostname_B = 'hB'

    # hA LO (loopback)
    loA_v4_host_address = ipaddress.ip_address('10.255.255.0')
    loA_v6_host_address = ipaddress.ip_address('dead:beef::0')
    loA_host_addresses = HostAddresses(v4=loA_v4_host_address,
                                       v6=loA_v6_host_address)
    new_service_host(hostname=hostname_A+"_LO",
                     host_addresses=loA_host_addresses,
                     cname_aliases=["alias1.hA", "alias2.hA"],
                     service_type='LO')

    # hB LO (loopback)
    new_service_host(hostname=hostname_B+"_LO",
                     cname_aliases=["alias1.hB"],
                     service_type='LO')

    # hA-hB TRUNK
    trunkAB_network_extattrs = {
        "vrf_name": {"value": "dummy_vrf"},
    }
    trunkAB_host_extattrs = {
        "Site": {"value": "dummy_site"},
    }
    trunkAB_service_networks = new_service_networks(
        service_type='TRUNK',
        extattrs=trunkAB_network_extattrs,
        comment="Network for hA-hB TRUNK"
    )

    trunkAB_v4_host_address = trunkAB_service_networks.v4.network_address
    trunkAB_v6_host_address = trunkAB_service_networks.v6.network_address
    trunkAB_host_addresses = HostAddresses(v4=trunkAB_v4_host_address,
                                           v6=trunkAB_v6_host_address)

    new_service_host(hostname=hostname_A+"_TRUNK",
                     service_type='TRUNK',
                     host_addresses=trunkAB_host_addresses,
                     extattrs=trunkAB_host_extattrs)

    new_service_host(hostname=hostname_B+"_TRUNK",
                     service_type='TRUNK',
                     service_networks=trunkAB_service_networks,
                     extattrs=trunkAB_host_extattrs)

Host/network deletion

    # Delete network
    service_network = ipam.delete_service_network(
        network=ipaddress.ip_network('10.255.255.0/26'), service_type='LO'
    )

    # Delete host
    input_host_addresses = ipam.HostAddresses(
        v4=ipaddress.ip_address('10.255.255.1'),
        v6=ipaddress.ip_address('dead:beef::1')
    )
    host_addresses = ipam.delete_service_host(
        hostname='ha_lo',
        host_addresses=input_host_addresses,
        cname_aliases=['alias1.ha', 'alias2.ha'],
        service_type='LO'
    )