ZONE: the zone for the client VM. This zone must be in
the same region as the load balancer.
SUBNET: the subnet for the client VM.
Send IPv6 traffic to the load balancer
Now that you have configured your load balancer, you can test your deployment by
sending traffic to the load balancer's IP address. It might take a few minutes
for the load balancer configuration to propagate after you first deploy it.
Connect to the client VM instance.
gcloud compute ssh CLIENT_VM_NAME \
--zone=ZONE
Replace the following:
CLIENT_VM_NAME: the name of the client VM.
ZONE: the zone of the client VM.
Get the IP address of the load balancer.
To get the IPv6 address, use the following command.
Now that you have configured your load balancer, you can test your deployment by
sending traffic to the load balancer's IP address. It might take a few minutes
for the load balancer configuration to propagate after you first deploy it.
Connect to the client VM instance.
gcloud compute ssh CLIENT_VM_NAME \
--zone=ZONE
Replace the following:
CLIENT_VM_NAME: the name of the client VM.
ZONE: the zone of the client VM.
Get the IP address of the load balancer.
To get the IPv4 address, use the following command.
Replace IPV4_FORWARDING_RULE_NAME with the name of the
IPv4 forwarding rule.
Send traffic to the load balancer.
From clients with IPv4 connectivity, run the following command:
curl -m 10 -s http://LB_IPV4_ADDRESS:80
Replace LB_IPV4_ADDRESS with the IPv4 address of the
load balancer.
Test external TCP LB
Send IPv6 traffic to the load balancer
Now that you have configured your load balancer, you can test your deployment by
sending traffic to the load balancer's IP address. It might take a few minutes
for the load balancer configuration to propagate after you first deploy it.
Get the load balancer's IP address.
To get the IPv6 address, use the following command.
Replace IPV6_FORWARDING_RULE_NAME with the name of the
IPv6 forwarding rule.
Send traffic to your load balancer by using curl to contact its IP
address.
From clients with IPv6 connectivity, run the following command:
while true; do curl -m1 http://LB_IPV6_ADDRESS; done
Replace LB_IPV6_ADDRESS with the IPv6 address of the
load balancer.
For example, if the assigned IPv6 address is
[2001:db8:1:1:1:1:1:1/96]:80, the command is similar to the following:
while true; do curl -m1 http://[2001:db8:1:1:1:1:1:1]:80; done
Note the text returned by the curl command. The name of the backend VM
generating the response is displayed in that text; for example: Page served
from: VM_NAME.
The response from the curl command alternates randomly among the backend
instances. If your response is initially unsuccessful, you might need to wait
approximately 30 seconds for the configuration to be fully loaded and for
your instances to be marked healthy before trying again.
Send IPv4 traffic to the load balancer
Now that you have configured your load balancer, you can test your deployment by
sending traffic to the load balancer's IP address. It might take a few minutes
for the load balancer configuration to propagate after you first deploy it.
Get the load balancer's IP address.
To get the IPv4 address, use the following command.
Replace IPV4_FORWARDING_RULE_NAME with the name of the
IPv4 forwarding rule.
Send traffic to your load balancer by using curl to contact its IP
address.
From clients with IPv4 connectivity, run the following command:
while true; do curl -m1 LB_IPV4_ADDRESS; done
Replace LB_IPV4_ADDRESS with the IPv4 address of the
load balancer.
Note the text returned by the curl command. The name of the backend VM
generating the response is displayed in that text; for example: Page served
from: VM_NAME.
The response from the curl command alternates randomly among the backend
instances. If your response is initially unsuccessful, you might need to wait
approximately 30 seconds for the configuration to be fully loaded and for
your instances to be marked healthy before trying again.
[[["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,["# Test shared how-to NetLB test modules\n\nTest internal TCP LB\n--------------------\n\n### Create client VM\n\nThis example creates a client VM in the same region as the backends. You then\nsend traffic from the client to the load balancer.\n\nThe client VM can be in any zone in the same region as the load balancer, and it\ncan use any subnet in that region. \n\n### Console\n\n1. In the Google Cloud console, go to the **VM instances** page.\n\n [Go to VM instances](https://console.cloud.google.com/compute/instances)\n2. Click **Create instance**.\n\n3. In the **Name** field, enter a name.\n\n4. For **Region**, select the same region as the load balancer.\n\n5. For **Zone**, select a zone.\n\n6. Click **Networking**.\n\n7. Configure the following fields and click **Done**:\n\n - For **Network tags** , enter `allow-ssh`.\n - For **Network interfaces**, select a network and a subnet. You can use the same network and subnet as the backends.\n - For **IP stack type** , choose **IPv6 (single-stack)**.\n8. Click **Create**.\n\n### gcloud\n\n```\ngcloud compute instances create CLIENT_VM_NAME \\\n --zone=ZONE \\\n --image-family=debian-12 \\\n --image-project=debian-cloud \\\n --stack-type=IPV6_ONLY \\\n --tags=allow-ssh \\\n --subnet=SUBNET\n```\n\nReplace the following:\n\n- \u003cvar translate=\"no\"\u003eCLIENT_VM_NAME\u003c/var\u003e: the name of the client VM.\n- \u003cvar translate=\"no\"\u003eZONE\u003c/var\u003e: the zone for the client VM. This zone must be in the same region as the load balancer.\n- \u003cvar translate=\"no\"\u003eSUBNET\u003c/var\u003e: the subnet for the client VM.\n\n### Send IPv6 traffic to the load balancer\n\nNow that you have configured your load balancer, you can test your deployment by\nsending traffic to the load balancer's IP address. It might take a few minutes\nfor the load balancer configuration to propagate after you first deploy it.\n\n1. Connect to the client VM instance.\n\n ```\n gcloud compute ssh CLIENT_VM_NAME \\\n --zone=ZONE\n ```\n\n Replace the following:\n - \u003cvar translate=\"no\"\u003eCLIENT_VM_NAME\u003c/var\u003e: the name of the client VM.\n - \u003cvar translate=\"no\"\u003eZONE\u003c/var\u003e: the zone of the client VM.\n2. Get the IP address of the load balancer.\n\n To get the IPv6 address, use the following command. \n\n ```\n gcloud compute forwarding-rules describe IPV6_FORWARDING_RULE_NAME \\\n --region=REGION\n ```\n\n Replace \u003cvar translate=\"no\"\u003eIPV6_FORWARDING_RULE_NAME\u003c/var\u003e with the name of the\n IPv6 forwarding rule.\n3. Send traffic to the load balancer.\n\n From clients with IPv6 connectivity, run the following command: \n\n ```\n curl -m 10 -s http://LB_IPV6_ADDRESS:80\n ```\n\n Replace \u003cvar translate=\"no\"\u003eLB_IPV6_ADDRESS\u003c/var\u003e with the IPv6 address of the\n load balancer.\n\n For example, if the assigned IPv6 address is\n `[fd20:1db0:b882:802:0:46:0:0/96]:80`, the command should look like: \n\n ```\n curl -m 10 -s http://[fd20:1db0:b882:802:0:46:0:0]:80\n ```\n\n### Send IPv4 traffic to the load balancer\n\nNow that you have configured your load balancer, you can test your deployment by\nsending traffic to the load balancer's IP address. It might take a few minutes\nfor the load balancer configuration to propagate after you first deploy it.\n\n1. Connect to the client VM instance.\n\n ```\n gcloud compute ssh CLIENT_VM_NAME \\\n --zone=ZONE\n ```\n\n Replace the following:\n - \u003cvar translate=\"no\"\u003eCLIENT_VM_NAME\u003c/var\u003e: the name of the client VM.\n - \u003cvar translate=\"no\"\u003eZONE\u003c/var\u003e: the zone of the client VM.\n2. Get the IP address of the load balancer.\n\n To get the IPv4 address, use the following command. \n\n ```\n gcloud compute forwarding-rules describe IPV4_FORWARDING_RULE_NAME \\\n --region=REGION\n ```\n\n Replace \u003cvar translate=\"no\"\u003eIPV4_FORWARDING_RULE_NAME\u003c/var\u003e with the name of the\n IPv4 forwarding rule.\n3. Send traffic to the load balancer.\n\n From clients with IPv4 connectivity, run the following command: \n\n ```\n curl -m 10 -s http://LB_IPV4_ADDRESS:80\n ```\n\n Replace \u003cvar translate=\"no\"\u003eLB_IPV4_ADDRESS\u003c/var\u003e with the IPv4 address of the\n load balancer.\n\nTest external TCP LB\n--------------------\n\n### Send IPv6 traffic to the load balancer\n\nNow that you have configured your load balancer, you can test your deployment by\nsending traffic to the load balancer's IP address. It might take a few minutes\nfor the load balancer configuration to propagate after you first deploy it.\n\n1. Get the load balancer's IP address.\n\n To get the IPv6 address, use the following command. \n\n ```\n gcloud compute forwarding-rules describe IPV6_FORWARDING_RULE_NAME \\\n --region=REGION\n ```\n\n Replace \u003cvar translate=\"no\"\u003eIPV6_FORWARDING_RULE_NAME\u003c/var\u003e with the name of the\n IPv6 forwarding rule.\n2. Send traffic to your load balancer by using `curl` to contact its IP\n address.\n\n From clients with IPv6 connectivity, run the following command: \n\n ```\n while true; do curl -m1 http://LB_IPV6_ADDRESS; done\n ```\n\n Replace \u003cvar translate=\"no\"\u003eLB_IPV6_ADDRESS\u003c/var\u003e with the IPv6 address of the\n load balancer.\n\n For example, if the assigned IPv6 address is\n `[2001:db8:1:1:1:1:1:1/96]:80`, the command is similar to the following: \n\n ```\n while true; do curl -m1 http://[2001:db8:1:1:1:1:1:1]:80; done\n ```\n\n Note the text returned by the `curl` command. The name of the backend VM\n generating the response is displayed in that text; for example: `Page served\n from: `\u003cvar translate=\"no\"\u003eVM_NAME\u003c/var\u003e.\n\n The response from the `curl` command alternates randomly among the backend\n instances. If your response is initially unsuccessful, you might need to wait\n approximately 30 seconds for the configuration to be fully loaded and for\n your instances to be marked healthy before trying again.\n\n### Send IPv4 traffic to the load balancer\n\nNow that you have configured your load balancer, you can test your deployment by\nsending traffic to the load balancer's IP address. It might take a few minutes\nfor the load balancer configuration to propagate after you first deploy it.\n\n1. Get the load balancer's IP address.\n\n To get the IPv4 address, use the following command. \n\n ```\n gcloud compute forwarding-rules describe IPV4_FORWARDING_RULE_NAME \\\n --region=REGION\n ```\n\n Replace \u003cvar translate=\"no\"\u003eIPV4_FORWARDING_RULE_NAME\u003c/var\u003e with the name of the\n IPv4 forwarding rule.\n2. Send traffic to your load balancer by using `curl` to contact its IP\n address.\n\n From clients with IPv4 connectivity, run the following command: \n\n ```\n while true; do curl -m1 LB_IPV4_ADDRESS; done\n ```\n\n Replace \u003cvar translate=\"no\"\u003eLB_IPV4_ADDRESS\u003c/var\u003e with the IPv4 address of the\n load balancer.\n\n Note the text returned by the `curl` command. The name of the backend VM\n generating the response is displayed in that text; for example: `Page served\n from: `\u003cvar translate=\"no\"\u003eVM_NAME\u003c/var\u003e.\n\n The response from the `curl` command alternates randomly among the backend\n instances. If your response is initially unsuccessful, you might need to wait\n approximately 30 seconds for the configuration to be fully loaded and for\n your instances to be marked healthy before trying again."]]
