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Updating a Subnet

Function

This API is used to update information about a subnet.

Restrictions

When updating the allocation_pools field, neither gateway nor broadcast IP addresses can be included.

URI

PUT /v2.0/subnets/{subnet_id}

Request Message

Table 1 Request parameter

Parameter

Type

Mandatory

Description

subnet

Object

Yes

Specifies the subnet list. For details, see Table 2.

You must specify at least one attribute when updating a subnet.
Table 2 subnet objects

Attribute

Mandatory

Type

Description

name

No

String

Specifies the subnet name.

allocation_pools

No

Array of allocation_pool objects

Specifies the available IP address pool. For details about the allocation_pool objects, see Table 3.

Example: [ { "start": "10.0.0.2", "end": "10.0.0.251"} ]

The last three and the first IP addresses in each subnet are the ones reserved by the system. For example, in subnet 192.168.1.0/24, IP addresses 192.168.1.0, 192.168.1.253, 192.168.1.254, and 192.168.1.255 are reserved by the system. By default, the IP addresses reserved by the system are not in the IP address pool specified by allocation_pool.

When updating an IP address pool, the allocation_pool value can contain neither gateway nor broadcast IP addresses.

dns_nameservers

No

Array of strings

Specifies the DNS server address.

Instructions:

Example: "dns_nameservers": ["8.xx.xx.8","8.xx.xx.4"]

A maximum of five DNS server addresses are supported.

host_routes

No

Array of host_route objects

Specifies the static VM routes. For details, see Table 4.

Static routes are not supported, and entered information will be ignored.

enable_dhcp

No

Boolean

Specifies whether to enable the DHCP function. Value false indicates that the DHCP function is not enabled.

The value can only be true.
Table 3 allocation_pool objects

Parameter

Mandatory

Type

Description

start

No

String

Specifies the start IP address of a network pool.

end

No

String

Specifies the end IP address of a network pool.
Table 4 host_route objects

Parameter

Mandatory

Type

Description

destination

No

String

Specifies the destination subnet of a route.

nexthop

No

String

Specifies the next-hop IP address of a route.

Response Message

Table 5 Response parameter

Parameter

Type

Description

subnet

Object

Specifies the subnet list. For details, see Table 6.
Table 6 subnet objects

Attribute

Type

Description

id

String

Specifies the subnet ID.

This parameter is not mandatory when you query subnets.

name

String

Specifies the subnet name.

ip_version

Integer

Specifies the IP address version.

Only IPv4 address is supported.

ipv6_address_mode

String

Specifies the IPv6 addressing mode.

ipv6_ra_mode

String

Specifies the IPv6 route broadcast mode.

network_id

String

Specifies the ID of the network to which the subnet belongs.

cidr

String

Specifies the CIDR format.

Only the addresses in the 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 network segments are supported. In addition, the subnet mask cannot be greater than 28.

gateway_ip

String

The gateway IP address cannot conflict with IP addresses configured for allocation_pools.

This attribute cannot be modified.

allocation_pools

Array of allocation_pool objects

Specifies the available IP address pool. For details, see the allocation_pool objects.

Table 7

Example: [ { "start": "10.0.0.2", "end": "10.0.0.251"} ]

The last three and the first IP addresses in each subnet are the ones reserved by the system. For example, in subnet 192.168.1.0/24, IP addresses 192.168.1.0, 192.168.1.253, 192.168.1.254, and 192.168.1.255 are reserved by the system. By default, the IP addresses reserved by the system are not in the IP address pool specified by allocation_pool.

When updating an IP address pool, the allocation_pool value can contain neither gateway nor broadcast IP addresses.

dns_nameservers

Array of strings

Specifies the DNS server address.

Example: "dns_nameservers": ["8.xx.xx.8","8.xx.xx.4"]

host_routes

Array of host_route objects

Specifies the static VM routes. For details, see Table 8.

Static routes are not supported, and entered information will be ignored.

tenant_id

String

Specifies the project ID.

enable_dhcp

Boolean

Specifies whether to enable the DHCP function. Value false indicates that the DHCP function is not enabled.

The value can only be true.

project_id

String

Specifies the project ID. For details about how to obtain a project ID, see Obtaining a Project ID.

created_at

String

Specifies the time (UTC) when the subnet is created.

Format: yyyy-MM-ddTHH:mm:ss

updated_at

String

Specifies the time (UTC) when the subnet is updated.

Format: yyyy-MM-ddTHH:mm:ss
Table 7 allocation_pool objects

Parameter

Type

Remarks

start

String

Specifies the start IP address of a network pool.

end

String

Specifies the end IP address of a network pool.
Table 8 host_route objects

Parameter

Type

Remarks

destination

String

Specifies the destination subnet of a route.

nexthop

String

Specifies the next-hop IP address of a route.

Example:

Example request

PUT https://{Endpoint}/v2.0/subnets/98bac90c-0ba7-4a63-8995-097da9bead1c  

{
  "subnet": {
    "name": "subnet-test"
  }
}

Example response

{
    "subnet": {
        "name": "subnet-test",
        "cidr": "172.16.2.0/24",
        "id": "98bac90c-0ba7-4a63-8995-097da9bead1c",
        "enable_dhcp": true,
        "network_id": "0133cd73-34d4-4d4c-bf1f-e65b24603206",
        "tenant_id": "bbfe8c41dd034a07bebd592bf03b4b0c",
        "project_id": "bbfe8c41dd034a07bebd592bf03b4b0c",
        "dns_nameservers": [],
        "allocation_pools": [
            {
                "start": "172.16.2.2",
                "end": "172.16.2.251"
            }
        ],
        "host_routes": [],
        "ip_version": 4,
        "gateway_ip": "172.16.2.1",
        "created_at": "2018-09-20T02:02:16",
        "updated_at": "2018-09-20T02:03:03"
    }
}

Status Code

See Status Codes.

Error Code

See Error Codes.

Parent topic: Subnet