Stay organized with collections
Save and categorize content based on your preferences.
Update the base route priority
When you configure a Border Gateway Protocol (BGP) session on a
Cloud Router, you can specify a base advertised priority. Before you
begin, ensure that you are familiar with the Cloud Router Advertised
routes overview.
For more information about how Cloud Router uses the base advertised
priority, see Advertised
priority.
Base priorities are whole numbers from 0 to 65535. The highest possible base
priority is 0. The default base priority is 100. If you don't specify a base
priority, the default priority is used.
Base priorities let you specify which Cloud VPN tunnels or
Cloud Interconnect VLAN attachments on-premises systems to use to send
packets to your VPC network. You can create active-active,
active-passive, or a custom combination of these topologies by using the base
priority to influence how packets are sent to your VPC network.
For an example using HA VPN tunnels, see Active-active
and active-passive routing options for
HA VPN
in the Cloud VPN documentation.
When choosing base priorities, keep the following in mind:
Region-to-region costs are between 201 and 9999, inclusive. The value
depends on the distance, latency, and other factors between two regions.
Google generates the region-to-region cost values, and you can't modify
them.
Base priorities among Cloud Routers in a region are recommended to
be between 0 and 200, inclusive. Because region-to-region costs are at
least 201, if you use base priorities of 201 or more, you might
accidentally assign a Cloud VPN tunnel or VLAN attachment a lower
priority than you intend. Another BGP session in a different region might
advertise the same prefix with an overall higher priority (MED, which equals
base priority plus region-to-region cost). Without carefully setting base
priorities in other regions, you might cause on-premises traffic to be
delivered to your VPC network by way of an unexpected
Cloud VPN tunnel or VLAN attachment.
Base priorities of 10200 or more help ensure that a prefix's overall
advertised priority (MED, base priority plus region-to-region cost) is
always lower than any other advertised prefix with a base priority of 200
or less.
To update the base advertised route priority for an existing BGP session,
follow these steps.
Console
For Cloud VPN tunnels that use dynamic routing, including
HA VPN tunnels, complete the following steps:
In the Google Cloud console, go to the Cloud VPN tunnels page.
From the list of attachments in the Name column, select the
attachment that you want to modify.
On the VLAN attachment details page, select the name of the
BGP session.
Modify the Advertised route priority value.
Click Save and continue.
gcloud
Run the update-bgp-peer command using the
--advertised-route-priority flag. Specify the name of the
Cloud Router and BGP session that correspond to the appropriate
Cloud VPN tunnel or VLAN attachment.
Use the
routers.patch
method to update the bgpPeers[] field.
The bgpPeers[] field accepts an array of BGP peers. When you PATCH this
field, you overwrite the existing array of BGP peers with the new array
included in your request.
Send a GET request to get the current array of BGP peers for the router.
For details, see
View BGP session configuration.
Send a PATCH request with a new array of BGP peers.
In the array element that contains the BGP session that you want to update,
modify the value of advertisedRoutePriority.
[[["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 2025-08-29 UTC."],[],[],null,["# Update the base route priority\n==============================\n\nWhen you configure a Border Gateway Protocol (BGP) session on a\nCloud Router, you can specify a base advertised priority. Before you\nbegin, ensure that you are familiar with the Cloud Router [Advertised\nroutes overview](/network-connectivity/docs/router/concepts/advertised-routes).\nFor more information about how Cloud Router uses the base advertised\npriority, see [Advertised\npriority](/network-connectivity/docs/router/concepts/advertised-routes#advertised-priority).\n\nBase priorities are whole numbers from `0` to `65535`. The highest possible base\npriority is `0`. The default base priority is `100`. If you don't specify a base\npriority, the default priority is used.\n\nBase priorities let you specify which Cloud VPN tunnels or\nCloud Interconnect VLAN attachments on-premises systems to use to send\npackets to your VPC network. You can create active-active,\nactive-passive, or a custom combination of these topologies by using the base\npriority to influence how packets are sent to your VPC network.\nFor an example using HA VPN tunnels, see [Active-active\nand active-passive routing options for\nHA VPN](/network-connectivity/docs/vpn/concepts/overview#active)\nin the Cloud VPN documentation.\n\nWhen choosing base priorities, keep the following in mind:\n\n- Region-to-region costs are between `201` and `9999`, inclusive. The value\n depends on the distance, latency, and other factors between two regions.\n Google generates the region-to-region cost values, and you can't modify\n them.\n\n- Base priorities among Cloud Routers in a region are recommended to\n be between `0` and `200`, inclusive. Because region-to-region costs are at\n least `201`, if you use base priorities of `201` or more, you might\n accidentally assign a Cloud VPN tunnel or VLAN attachment a lower\n priority than you intend. Another BGP session in a different region might\n advertise the same prefix with an overall higher priority (MED, which equals\n base priority plus region-to-region cost). Without carefully setting base\n priorities in other regions, you might cause on-premises traffic to be\n delivered to your VPC network by way of an unexpected\n Cloud VPN tunnel or VLAN attachment.\n\n- Base priorities of `10200` or more help ensure that a prefix's overall\n advertised priority (MED, base priority plus region-to-region cost) is\n always lower than any other advertised prefix with a base priority of `200`\n or less.\n\nTo update the base advertised route priority for an existing BGP session,\nfollow these steps. \n\n### Console\n\nFor Cloud VPN tunnels that use dynamic routing, including\nHA VPN tunnels, complete the following steps:\n\n1. In the Google Cloud console, go to the **Cloud VPN** tunnels page.\n\n [Go to Cloud VPN tunnels](https://console.cloud.google.com/hybrid/vpn/list?&tab=tunnels)\n2. From the list of tunnels in the **Name** column, select the\n tunnel that you want to modify.\n\n3. On the **Cloud VPN tunnel details** page, select\n **Modify BGP session**.\n\n4. Modify the **Advertised route priority** value.\n\n5. Click **Save and continue**.\n\nFor Dedicated Interconnect or Partner Interconnect,\ncomplete the following steps:\n\n1. In the Google Cloud console, go to the **VLAN attachments** tab on the\n **Cloud Interconnect** page.\n\n [Go to Cloud Interconnect](https://console.cloud.google.com/hybrid/interconnects/list?&tab=attachments)\n2. From the list of attachments in the **Name** column, select the\n attachment that you want to modify.\n\n3. On the **VLAN attachment details** page, select the name of the\n **BGP session**.\n\n4. Modify the **Advertised route priority** value.\n\n5. Click **Save and continue**.\n\n### gcloud\n\nRun the `update-bgp-peer` command using the\n`--advertised-route-priority` flag. Specify the name of the\nCloud Router and BGP session that correspond to the appropriate\nCloud VPN tunnel or VLAN attachment. \n\n```\ngcloud compute routers update-bgp-peer ROUTER_NAME \\\n --peer-name=NAME_OF_BGP_SESSION \\\n --advertised-route-priority=BASE_PRIORITY_VALUE\n```\n\n### API\n\nUse the\n[`routers.patch`](/compute/docs/reference/rest/v1/routers/patch)\nmethod to update the `bgpPeers[]` field.\n\nThe `bgpPeers[]` field accepts an array of BGP peers. When you `PATCH` this\nfield, you overwrite the existing array of BGP peers with the new array\nincluded in your request.\n\n1. Send a `GET` request to get the current array of BGP peers for the router.\n For details, see\n [View BGP session configuration](/network-connectivity/docs/router/how-to/viewing-router-details#bgp-configuration).\n\n2. Send a `PATCH` request with a new array of BGP peers.\n In the array element that contains the BGP session that you want to update,\n modify the value of `advertisedRoutePriority`.\n\n ```\n PATCH https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/regions/REGION/routers/ROUTER_NAME\n {\n \"bgpPeers\": [\n BGP_PEERS\n ]\n }\n ```\n\n Replace the following:\n - \u003cvar translate=\"no\"\u003ePROJECT_ID\u003c/var\u003e: the project that contains the Cloud Router\n - \u003cvar translate=\"no\"\u003eREGION\u003c/var\u003e: the region where the Cloud Router is located\n - \u003cvar translate=\"no\"\u003eROUTER_NAME\u003c/var\u003e: the name of the Cloud Router\n - \u003cvar translate=\"no\"\u003eBGP_PEERS\u003c/var\u003e: the contents of the new array of BGP peers\n\n The following example includes one BGP peer with the default\n `advertisedRoutePriority` of `100` and another with an updated value\n of `99`: \n\n ```\n {\n \"name\": \"peer-1\",\n \"interfaceName\": \"if-peer-1\",\n \"ipAddress\": \"169.254.10.1\",\n \"peerIpAddress\": \"169.254.10.2\",\n \"peerAsn\": 64512,\n \"advertisedRoutePriority\": 100,\n \"advertiseMode\": \"DEFAULT\"\n },\n {\n \"name\": \"peer-2\",\n \"interfaceName\": \"if-peer-2\",\n \"ipAddress\": \"169.254.20.1\",\n \"peerIpAddress\": \"169.254.20.2\",\n \"peerAsn\": 64513,\n \"advertisedRoutePriority\": 99,\n \"advertiseMode\": \"DEFAULT\"\n }\n ```\n\nWhat's next?\n------------\n\n- To view the base advertised route priority, see\n [View Cloud Router details](/network-connectivity/docs/router/how-to/viewing-router-details).\n\n- To troubleshoot issues when using Cloud Router, see\n [Troubleshooting](/network-connectivity/docs/router/resources/troubleshooting)."]]