The section provides instructions for updating the description, capacity,
and maximum transmission unit (MTU) of a VLAN attachment. Changing the
attributes of a VLAN attachment, in rare cases, can cause traffic disruption.
If traffic is disrupted, the disruption typically lasts less than a minute.
To make use of the 1500-byte MTU, the VPC network that uses
the attachment must have an MTU set to 1500.
In addition, the remote cloud resources must have an MTU set to1500.
If your network has the default MTU of 1460, leave the field at 1440.
Console
In the Google Cloud console, go to the Cloud Interconnect
VLAN attachments tab.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[],[],null,["# Modify VLAN attachments\n\nThis document describes how to modify VLAN attachments and Border Gateway\nProtocol (BGP) sessions for Cross-Cloud Interconnect.\n| **Note:** For definitions of terms used on this page, see [Cloud Interconnect key terms](/network-connectivity/docs/interconnect/concepts/terminology).\n\nThe following table describes properties of VLAN attachments and their BGP\nsessions, along with information about how to modify them.\n\nModify description, capacity, and MTU\n-------------------------------------\n\nThe section provides instructions for updating the description, capacity,\nand maximum transmission unit (MTU) of a VLAN attachment. Changing the\nattributes of a VLAN attachment, in rare cases, can cause traffic disruption.\nIf traffic is disrupted, the disruption typically lasts less than a minute.\n\nTo make use of the 1500-byte MTU, the VPC network that uses\nthe attachment must have an [MTU](/vpc/docs/mtu) set to `1500`.\nIn addition, the remote cloud resources must have an MTU set to`1500`.\nIf your network has the default MTU of `1460`, leave the field at `1440`. \n\n### Console\n\n1. In the Google Cloud console, go to the Cloud Interconnect\n **VLAN attachments** tab.\n\n [Go to VLAN attachments](https://console.cloud.google.com/hybrid/interconnects/list?tab=attachments)\n2. Select the VLAN attachment to modify.\n\n3. On the attachment's detail page, click **Edit**.\n\n4. Modify your VLAN attachment:\n\n - **Description**: Information about the VLAN attachment.\n - **Capacity**: The maximum bandwidth of the attachment.\n - **Maximum transmission unit (MTU)**: The MTU of the attachment.\n5. Click **Save**.\n\n### gcloud\n\nUse the\n[`gcloud compute interconnects attachments dedicated update` command](/sdk/gcloud/reference/compute/interconnects/attachments/dedicated/update): \n\n```\ngcloud compute interconnects attachments dedicated update NAME \\\n --region=REGION \\\n --description=DESCRIPTION \\\n --bandwidth=BANDWIDTH \\\n --mtu MTU\n```\n\nReplace the following:\n\n- \u003cvar translate=\"no\"\u003eNAME\u003c/var\u003e: the name of the VLAN attachment\n- \u003cvar translate=\"no\"\u003eREGION\u003c/var\u003e: the region of the attachment\n- \u003cvar translate=\"no\"\u003eDESCRIPTION\u003c/var\u003e: a description of the attachment\n- \u003cvar translate=\"no\"\u003eBANDWIDTH\u003c/var\u003e: the provisioned capacity of the attachment\n- \u003cvar translate=\"no\"\u003eMTU\u003c/var\u003e: the MTU of the attachment\n\nWhat's next\n-----------\n\n- To learn more about Cross-Cloud Interconnect, see the\n [Cross-Cloud Interconnect overview](/network-connectivity/docs/interconnect/concepts/cci-overview).\n\n- To help you solve common issues that you might encounter when using\n Cloud Interconnect, see\n [Troubleshooting](/network-connectivity/docs/interconnect/support/troubleshooting#cci)."]]
