---
title: "Attach a security group to a node"
description: "Attach a security group to a node from the node's Security Group tab, so the group's rules control traffic to and from the node."
content_type: "how-to"
product: "security-group"
platform: "MyAccount"
url: "/myaccount/security-group/how-to/attach-a-security-group-to-a-node/"
topic: ["attach"]
relationships: {"requires":["/myaccount/node/how-to/create-a-node/","/myaccount/security-group/how-to/create-a-security-group/"]}
---

# Attach a security group to a node

Attaching a security group to a node puts its rules to work there. A node can carry several
groups, and their rules add up: traffic gets through when any one of them allows it.

## Before you begin

- A node in your account. See [Create a node](/myaccount/node/how-to/create-a-node/).
- The security group to attach. See [Create a security group](/myaccount/security-group/how-to/create-a-security-group/).

## Attach the group

1. Open **Compute > Nodes**, select the node, and open its **Security Group** tab.
2. Click **Attach Security Group**.
3. Type part of the group's name, pick the group, and pick more if you want to attach several
   at once.
4. Click the check mark.

The group joins the list on the node's **Security Group** tab, and its rules now apply to the
node. Expand a group in the list to see its inbound and outbound rules, or click the
edit icon beside it to change them. If the picker has no
group left to offer, the tab says **No more Security Groups are available.** and links to
creating one.

## Make the new group the one that decides

If you attached the group to be stricter, such as SSH from your office only, check the other
groups on the node. The default group allows all traffic from anywhere, so while it stays attached, a
rule that limits SSH to your office makes no difference. Once your group is
attached, [detach the default group](/myaccount/security-group/how-to/detach-a-security-group-from-a-node/)
from the node.

The node now follows the rules of every group on its list. To change what a group allows, see [Add or edit rules](/myaccount/security-group/how-to/add-or-edit-rules/). A group that will not attach is covered in [Troubleshooting Security Group](/myaccount/security-group/troubleshooting/security-group/).