--- title: "BGP peer" description: "Reference for the BGPPeer resource in Calico Open Source that defines a BGP neighbor relationship between Calico nodes and external routers." product: "Calico Open Source" version: "3.32 (latest)" section: "Reference" canonical_url: "https://docs.tigera.io/calico/latest/reference/resources/bgppeer" --- # BGP peer A BGP peer resource (`BGPPeer`) represents a remote BGP peer with which the node(s) in a Calico cluster will peer. Configuring BGP peers allows you to peer a Calico network with your datacenter fabric (e.g. ToR). For more information on cluster layouts, see Calico's documentation on [Calico over IP fabrics](https://docs.tigera.io/calico/latest/reference/architecture/design/l3-interconnect-fabric.md). ## Sample YAML ```yaml apiVersion: projectcalico.org/v3 kind: BGPPeer metadata: name: some.name spec: node: rack1-host1 peerIP: 192.168.1.1 asNumber: 63400 ``` ## BGP peer definition ### Metadata | Field | Description | Accepted Values | Schema | | ----- | ------------------------------------------------------------------ | --------------------------------------------------- | ------ | | name | Unique name to describe this resource instance. Must be specified. | Alphanumeric string with optional `.`, `_`, or `-`. | string | ### Spec | Field | Description | Accepted Values | Schema | Default | | ------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------- | ------------------------------------------------------------- | ---------------------------------------------------------------------------- | | node | If specified, the scope is node level, otherwise the scope is global. | The hostname of the node to which this peer applies. | string | | | peerIP | The IP address of this peer and an optional port number. If port number is not set, and peer is Calico node with `listenPort` set, then `listenPort` is used. | Valid IPv4 or IPv6 address. If port number is set use, `IPv4:port` or `[IPv6]:port` format. | string | | | asNumber | The remote AS Number of the peer. | A valid AS Number, may be specified in dotted notation. | integer/string | | | localASNumber | Specifies AS Number Calico uses as its local AS Number for this peer, overriding the global AS Number set in the default BGPConfiguration. | A valid AS Number, may be specified in dotted notation. | integer/string | | | nodeSelector | Selector for the nodes that should have this peering. When this is set, the `node` field must be empty. | | [selector](#selectors) | | | peerSelector | Selector for the remote nodes to peer with. When this is set, the `peerIP` and `asNumber` fields must be empty. | | [selector](#selectors) | | | localWorkloadSelector | Selector for the local workloads that the node should peer with. When this is set, the `peerSelector` and `peerIP` fields must be empty and the `localWorkloadPeeringIPV4` and/or `localWorkloadPeeringIPV6` fields in the `BGPConfiguration` resource must be configured. It is also important to configure appropriate import/export filters when using this feature. See the [guide](https://docs.tigera.io/calico/latest/networking/configuring/bgp-to-workload.md) for details. | | [selector](#selectors) | | | keepOriginalNextHop | Maintain and forward the original next hop BGP route attribute to a specific Peer within a different AS. Note: this field is deprecated. Users should use the nextHopMode field to control the next hop attribute for a BGP peer. | | boolean | | | password | BGP password for the peerings generated by this BGPPeer resource. | | [BGPPassword](#bgppassword) | `nil` (no password) | | sourceAddress | Specifies whether and how to configure a source address for the peerings generated by this BGPPeer resource. Default value "UseNodeIP" means to configure the node IP as the source address. "None" means not to configure a source address. | "UseNodeIP", "None" | string | "UseNodeIP" | | maxRestartTime | Restart time that is announced by BIRD in the BGP graceful restart capability and that specifies how long the neighbor would wait for the BGP session to re-establish after a restart before deleting stale routes. Note: extra care should be taken when changing this configuration, as it may break networking in your cluster. When not specified, BIRD uses the default value of 120 seconds. | `10s`, `120s`, `2m` etc. | [Duration string](https://golang.org/pkg/time/#ParseDuration) | `nil` (empty config, BIRD will use the default value of `120s`) | | numAllowedLocalASNumbers | The number of local AS numbers to allow in the AS path for received routes. This disables BGP loop prevention and should only be used if necessary. | | integer | `nil` (BIRD will default to 0 meaning no change to loop prevention behavior) | | ttlSecurity | Enables the generalized TTL security mechanism (GTSM) which protects against spoofed packets by ignoring received packets with a smaller than expected TTL value. The provided value is the number of hops (edges) between the peers. | 0 - 255 | 8-bit integer | `nil` (results in BIRD configuration `ttl security off`) | | filters | List of names of [BGPFilter](https://docs.tigera.io/calico/latest/reference/resources/bgpfilter.md) resources to apply to this peering. | \[ "my-calico-bgp-filter1","my-calico-bgp-filter2" ] | List of strings | | | reachableBy | Adds a static route that may be needed to connect to a peer. In some cases, not having a static route for BGP peering results in route flapping. By adding the address of the gateway that the peer is connected to, a static route is added to prevent route flapping. | The address of the gateway that the peer is connected to | string | | | nextHopMode | Specifies the method of calculating the next hop attribute for received routes. This replaces and expands the deprecated KeepOriginalNextHop field. Users should use this setting to control the next hop attribute for a BGP peer. When this is set, the value of the keepOriginalNextHop field is ignored. If neither keepOriginalNextHop or nextHopMode is specified, BGP's default behavior is used. Default value “Auto” means to apply BGP’s default behavior. "Self" means to configure "next hop self;" in "bird.cfg". "Keep" means to configure "next hop keep;" in "bird.cfg". | "Auto", "Self", "Keep" | string | "Auto" | | reversePeering | Specifies whether Calico automatically generates reverse peerings for nodes selected by the peerSelector. If set to Manual, a separate BGPPeer must be created for the reverse peering. | "Auto", "Manual" | string | "Auto" | > **SUCCESS:** The cluster-wide default local AS number used when speaking with a peer is controlled by the [BGPConfiguration resource](https://docs.tigera.io/calico/latest/reference/resources/bgpconfig.md). That value can be overridden per-node by using the `bgp` field of the [node resource](https://docs.tigera.io/calico/latest/reference/resources/node.md). > **SECONDARY:** If you want to use `BGPPeer` resources to configure BGP sessions between nodes within the cluster - for example, to set non-default BGPPeer parameters - you must disable node-to-node mesh by setting the `nodeToNodeMeshEnabled` parameter to false in the [BGPConfiguration](https://docs.tigera.io/calico/latest/reference/resources/bgpconfig.md) resource. ### BGPPassword > **SECONDARY:** BGP passwords must be 80 characters or fewer. If a password longer than that is configured, the BGP sessions with that password will fail to be established. | Field | Description | Schema | | ------------ | ------------------------------- | ----------------- | | secretKeyRef | Get the password from a secret. | [KeyRef](#keyref) | ### KeyRef KeyRef tells Calico where to get a BGP password. The referenced Kubernetes secret must be in the same namespace as the calico/node pod. | Field | Description | Schema | | ----- | ------------------------- | ------ | | name | The name of the secret | string | | key | The key within the secret | string | > **WARNING:** Calico must be able to read the referenced secret. > > This means that the `calico-node` ServiceAccount must have permissions to `list, get, watch` the secret referenced in the KeyRef. > > In practice, this can be done by creating a Role (which allows to `list, get, watch` the secret) and a RoleBinding (which grants the Role's permission to the `calico-node` ServiceAccount). > > Example: > > ```yaml > --- > apiVersion: rbac.authorization.k8s.io/v1 > kind: Role > metadata: > name: bgp-passwords-reader > namespace: calico-system # Or kube-system if installed using manifests. > rules: > - apiGroups: [""] > resources: ["secrets"] > resourceNames: ["bgp-passwords"] > verbs: ["list", "watch", "get"] > > --- > apiVersion: rbac.authorization.k8s.io/v1 > kind: RoleBinding > metadata: > name: calico-read-bgp-passwords > namespace: calico-system # Or kube-system if installed using manifests. > roleRef: > apiGroup: rbac.authorization.k8s.io > kind: Role > name: bgp-passwords-reader > subjects: > - kind: ServiceAccount > name: calico-node > > --- > apiVersion: v1 > kind: Secret > metadata: > name: "bgp-passwords" > namespace: calico-system # Or kube-system if installed using manifests. > data: > peer_a_pw: "base64-encoded Password for Peer A" > peer_b_pw: "base64-encoded Password for Peer B" > > --- > apiVersion: projectcalico.org/v3 > kind: BGPPeer > metadata: > name: "peer-a" > spec: > password: > secretKeyRef: > name: "bgp-passwords" > key: "peer_a_pw" > > --- > apiVersion: projectcalico.org/v3 > kind: BGPPeer > metadata: > name: "peer-b" > spec: > password: > secretKeyRef: > name: "bgp-passwords" > key: "peer_b_pw" > ``` ## Peer scopes BGP Peers can exist at either global or node-specific scope. A peer's scope determines which `calico/node`s will attempt to establish a BGP session with that peer. If `calico/node` has a `listenPort` set in `BGPConfiguration`, it will be used in peering. ### Global peer To assign a BGP peer a global scope, omit the `node` and `nodeSelector` fields. All nodes in the cluster will attempt to establish BGP connections with it ### Node-specific peer A BGP peer can also be node-specific. When the `node` field is included, only the specified node will peer with it. When the `nodeSelector` field is included, the nodes with labels that match that selector will peer with it. ## Selectors A label selector is an expression which either matches or does not match a resource based on its labels. Calico label selectors support a number of operators, which can be combined into larger expressions using the boolean operators and parentheses. | Expression | Meaning | | ------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | **Logical operators** | | | `( )` | Matches if and only if `` matches. (Parentheses are used for grouping expressions.) | | `! ` | Matches if and only if `` does not match. **Tip:** `!` is a special character at the start of a YAML string, if you need to use `!` at the start of a YAML string, enclose the string in quotes. | | ` && ` | "And": matches if and only if both ``, and, `` matches | | ` \|\| ` | "Or": matches if and only if either ``, or, `` matches. | | **Match operators** | | | `all()` | Match all in-scope resources. To match *no* resources, combine this operator with `!` to form `!all()`. | | `global()` | Match all non-namespaced resources. Useful in a `namespaceSelector` to select global resources such as global network sets. | | `k == 'v'` | Matches resources with the label 'k' and value 'v'. | | `k != 'v'` | Matches resources without label 'k' or with label 'k' and value *not* equal to `v` | | `has(k)` | Matches resources with label 'k', independent of value. To match pods that do not have label `k`, combine this operator with `!` to form `!has(k)` | | `k in { 'v1', 'v2' }` | Matches resources with label 'k' and value in the given set | | `k not in { 'v1', 'v2' }` | Matches resources without label 'k' or with label 'k' and value *not* in the given set | | `k contains 's'` | Matches resources with label 'k' and value containing the substring 's' | | `k starts with 's'` | Matches resources with label 'k' and value starting with the substring 's' | | `k ends with 's'` | Matches resources with label 'k' and value ending with the substring 's' | Operators have the following precedence: - **Highest**: all the match operators - Parentheses `( ... )` - Negation with `!` - Conjunction with `&&` - **Lowest**: Disjunction with `||` For example, the expression ```text ! has(my-label) || my-label starts with 'prod' && role in {'frontend','business'} ``` Would be "bracketed" like this: ```text ((!(has(my-label)) || ((my-label starts with 'prod') && (role in {'frontend','business'})) ``` It would match: - Any resource that did not have label "my-label". - Any resource that both: - Has a value for `my-label` that starts with "prod", and, - Has a role label with value either "frontend", or "business".