Modify VLAN attachments

This document describes how to modify Partner Interconnect VLAN attachments and their Border Gateway Protocol (BGP) sessions.

The following table lists VLAN attachment and BGP session properties. It also provides information about how to modify them.

Property	How to modify
Capacity	Work with your service provider as described in the Modify capacity section in this document.
Description and MTU	See the Modify the description and MTU section in this document. Modifications are immediate and in rare cases can cause traffic disruption. If traffic is disrupted, the disruption lasts less than a minute.
Stack type	See the Modify the stack type section in this document. Modifying the stack type from IPv4 and IPv6 (dual stack) to IPv4 only (single stack) removes the IPv6 BGP session from the associated Cloud Router, and removes the IPv6 address from the VLAN attachment. Changing the stack type on an IPv4 only (single stack) attachment to IPv4 and IPv6 (dual stack) adds a default-configured IPv6 BGP session to the associated Cloud Router. The following describes the behavior of the IPv6 BGP session: The attachment is active and the peer router already has an IPv6 BGP configuration: the IPv6 BGP session establishes and starts routing IPv6 traffic immediately. The attachment isn't active or the peer router doesn't have an IPv6 BGP configuration: the IPv6 BGP session doesn't establish and you can modify the BGP session before activating the attachment or configuring the peer router. To change the stack type of an IPv4 only (single stack) attachment without immediately accepting IPv6 traffic, de-activate the attachment or disable the peer router's IPv6 BGP configuration first.
Whether a VLAN attachment is enabled or disabled	To disable or re-enable a VLAN attachment, see Disable VLAN attachments.
VLAN ID BGP IP addresses (Cloud Router IP address, on-premises router IP address)	You can't modify these properties for existing attachments. Instead, you must recreate the VLAN attachment. To create VLAN attachments for Partner Interconnect, see Create VLAN attachments.
Custom learned routes	Follow the steps in Update an existing session to use custom learned routes.
MD5 authentication	If you have a Layer 2 connection, follow the steps in Add authentication to an existing session. If you have a Layer 3 connection, contact your service provider for instructions.

The peer ASN is not a property of the VLAN attachment—it is part of the BGP configuration of the Cloud Router. If you have a Layer 2 connection and you want to modify the peer ASN, update the Cloud Router's BGP session for the VLAN attachment.

For more information, see the following resources:

Modify capacity

For an existing VLAN attachment, Google Cloud supports increasing or decreasing the attachment's capacity as your capacity demands rise or fall. Because capacity changes can affect your service provider's network, you must work with them to change your attachment's capacity. Changes in capacity, in rare cases, can cause traffic disruption. If traffic is disrupted, the disruption lasts less than a minute.

After the service provider has updated your attachment, your service provider works with Google to update the attachment's capacity in your Google Cloud project. At that time, Google updates the charges for the attachment based on the new capacity.

If you modify the capacity of an encrypted VLAN attachment, you might need to add HA VPN tunnels to accommodate increased traffic. For more information, see Configure HA VPN over Cloud Interconnect.

For a list of all the service providers, see Supported service providers.

Modify the description and MTU

This section provides instructions for updating the description and maximum transmission unit (MTU) of a VLAN attachment. In rare cases, changing the attributes of a VLAN attachment can cause traffic disruption. If traffic is disrupted, the disruption lasts less than a minute.

To make use of a 1460-, 1500-, or 8896-byte MTU, the VPC network that uses the attachment must have the same MTU value. In addition, the on-premises virtual machine (VM) instances and routers must have the same MTU value. If your network has the default MTU of 1460, then select an MTU of 1460 for your VLAN attachment.

You cannot modify the MTU (1440) of an encrypted VLAN attachment that is used in an HA VPN over Cloud Interconnect deployment.

Console

In the Google Cloud console, go to the Cloud Interconnect VLAN attachments tab.

Go to VLAN attachments
Select the VLAN attachment to modify.
On the attachment's detail page, click Edit.
Modify the Description of your VLAN attachment.
Optional: Update the maximum transmission unit (MTU) of the attachment.
Click Save.

gcloud

Modify an interconnectAttachment by specifying the name of the existing VLAN attachment and the attributes to modify:

gcloud compute interconnects attachments partner update NAME \
    --region=REGION \
    --description=DESCRIPTION \
    --mtu=MTU

Replace the following:

NAME: the name of the existing VLAN attachment
REGION: the region of the attachment
DESCRIPTION: a description of the attachment
MTU: the maximum transmission unit (MTU) of the attachment

For more information, see the gcloud compute interconnects attachments partner update reference.

Modify the stack type

This section describes modifying the stack type of a VLAN attachment. You can change between either IPv4 only (single stack), or IPv4 and IPv6 (dual stack).

Modifying the stack type from IPv4 and IPv6 (dual stack) to IPv4 only (single stack) removes the BGP session from the associated Cloud Router, and removes the IPv6 address from the VLAN attachment.

Console

In the Google Cloud console, go to the Cloud Interconnect VLAN attachments tab.

Go to VLAN attachments
Select the VLAN attachment to modify.
On the attachment's detail page, click Edit.
In the IP stack type section, select the IP stack type, either IPv4 (single-stack) or IPv4 and IPv6 (dual-stack).
Click Save.

gcloud

Run the following command:

gcloud compute interconnects attachments partner update NAME \
  --region=REGION \
  --stack_type=STACK_TYPE

Replace the following:

NAME: the name of the existing VLAN attachment.
REGION: the region of your VLAN attachment.
STACK_TYPE: the stack type for your VLAN attachment. The stack type can be one of the following:
- IPV4_ONLY: selects IPv4 only (single stack).
- IPV4_IPV6: selects IPv4 and IPv6 (dual stack).

The output is similar to the following when changing the stack type from IPV4_ONLY to IPV4_IPV6:

adminEnabled: true
edgeAvailabilityDomain: AVAILABILITY_DOMAIN_1
bandwidth: BPS_1G
cloudRouterIpAddress: 169.254.67.201/29
cloudRouterIpv6Address: 2600:2d00:0:1::1/125
creationTimestamp: '2017-12-01T08:31:11.580-08:00'
customerRouterIpAddress: 169.254.67.202/29
customerRouterIpv6Address: 2600:2d00:0:1::2/125
description: Interconnect for location 1
id: '7193021941765913888'
interconnect: https://www.googleapis.com/compute/alpha/projects/partner-project/global/interconnects/lga-2
kind: compute#interconnectAttachment
labelFingerprint: 42WmSpB8rSM=
name: partner-attachment
partnerMetadata:
interconnectName: New York (2)
partnerName: Partner Inc
portalUrl: https://partner-portal.com
region: https://www.googleapis.com/compute/alpha/projects/partner-project/regions/REGION
selfLink: https://www.googleapis.com/compute/alpha/projects/partner-project/regions/REGION/interconnectAttachments/ATTACHMENT_NAME
stackType: STACK_TYPE
state: ACTIVE
type: PARTNER
vlanTag8021q: 1000

The output is similar to the following when changing the stack type from IPV4_IPV6to IPV4_ONLY:

adminEnabled: true
edgeAvailabilityDomain: AVAILABILITY_DOMAIN_1
bandwidth: BPS_1G
cloudRouterIpAddress: 169.254.67.201/29
creationTimestamp: '2017-12-01T08:31:11.580-08:00'
customerRouterIpAddress: 169.254.67.202/29
description: Interconnect for location 1
id: '7193021941765913888'
interconnect: https://www.googleapis.com/compute/alpha/projects/partner-project/global/interconnects/lga-2
kind: compute#interconnectAttachment
labelFingerprint: 42WmSpB8rSM=
name: partner-attachment
partnerMetadata:
interconnectName: New York (2)
partnerName: Partner Inc
portalUrl: https://partner-portal.com
region: https://www.googleapis.com/compute/alpha/projects/partner-project/regions/REGION
selfLink: https://www.googleapis.com/compute/alpha/projects/partner-project/regions/REGION/interconnectAttachments/ATTACHMENT_NAME
stackType: STACK_TYPE
state: ACTIVE
type: PARTNER
vlanTag8021q: 1000

What's next

To create a Partner Interconnect connection, see the Partner Interconnect provisioning overview.
To learn more about Cloud Interconnect options, see the Cloud Interconnect overview.
To help you solve common issues that you might encounter when using Partner Interconnect, see Troubleshooting.