Amazon VPC Transit Gateways Quotas - Amazon VPC
GeneralRoutingTransit gateway attachmentsBandwidthAWS Direct Connect gatewaysMaximum transmission unit (MTU)MulticastNetwork ManagerAdditional quota resources

Amazon VPC Transit Gateways Quotas

Your AWS account has the following quotas (previously referred to as limits) related to transit gateways. Unless otherwise noted, each quota is Region-specific.

The Service Quotas console provides information about the quotas for your account. You can use the Service Quotas console to view default quotas and request quota increases for adjustable quotas. For more information, see Requesting a quota increase in the Service Quotas User Guide.

If an adjustable quota is not yet available in Service Quotas, you can open a support case.

General

Name Default Adjustable
Transit gateways per account 5 Yes
CIDR blocks per transit gateway 5 No

The CIDR blocks are used in the Transit Gateway Connect attachments and Transit Gateway Connect peers in Amazon VPC Transit Gateways feature.

Routing

Name Default Adjustable
Transit gateway route tables per transit gateway 20 Yes
Total combined routes (dynamic and static) across all route tables for a single transit gateway 10,000 Yes
Dynamic routes advertised from a virtual router appliance to a Connect peer 1,000 Yes
Routes advertised from a Connect peer on a transit gateway to a virtual router appliance 5,000 No
Static routes for a prefix to a single attachment 1 No

Advertised routes come from the route table that's associated with the Connect attachment.

Transit gateway attachments

A transit gateway cannot have more than one VPC attachment to the same VPC.

Name Default Adjustable
Attachments per transit gateway 5,000 No
Transit gateways per VPC 5 No
Peering attachments per transit gateway 50 Yes
Pending peering attachments per transit gateway 10 Yes
Peering attachments between two transit gateways or between one transit gateway and a Cloud WAN core network edge (CNE) 1 No
Connect peers (GRE tunnels) per Connect attachment 4 No

Bandwidth

There are many factors that can affect realized bandwidth through a Site-to-Site VPN connection, including but not limited to: packet size, traffic mix (TCP/UDP), shaping or throttling policies on intermediate networks, internet weather, and specific application requirements. For VPC attachments, AWS Direct Connect gateways, or peered transit gateway attachments, we will attempt to provide additional bandwidth beyond the default value.

Name Default Adjustable
Bandwidth per VPC attachment per Availability Zone Up to 100 Gbps Contact your Solutions Architect (SA) or Technical Account Manager (TAM) for further assistance.
Packets per second per transit gateway VPC attachment per Availability Zone Up to 7,500,000 Contact your Solutions Architect (SA) or Technical Account Manager (TAM) for further assistance.
Bandwidth for AWS Direct Connect gateway or peered transit gateway connection per available Availability Zone in the Region Up to 100 Gbps Contact your Solutions Architect (SA) or Technical Account Manager (TAM) for further assistance.
Packets per second per transit gateway attachment (AWS Direct Connect and peering attachments) per available Availability Zone in the Region Up to 7,500,000 Contact your Solutions Architect (SA) or Technical Account Manager (TAM) for further assistance.
Maximum bandwidth per VPN tunnel Up to 1.25 Gbps No
Maximum packets per second per VPN tunnel Up to 140,000 No
Maximum bandwidth per Connect peer (GRE tunnel) per Connect attachment Up to 5 Gbps No
Maximum packets per second per Connect peer Up to 300,000 No

You can use equal-cost multipath routing (ECMP) to get higher VPN bandwidth by aggregating multiple VPN tunnels. To use ECMP, the VPN connection must be configured for dynamic routing. ECMP is not supported on VPN connections that use static routing.

You can create up to 4 Connect peers per Connect attachment (up to 20 Gbps in total bandwidth per Connect attachment), as long as the underlying transport (VPC or AWS Direct Connect) attachment supports the required bandwidth. You can use ECMP to get higher bandwidth by scaling horizontally across multiple Connect peers of the same Connect attachment or across multiple Connect attachments on the same transit gateway. The transit gateway cannot use ECMP between the BGP peerings of the same Connect peer.

AWS Direct Connect gateways

Name Default Adjustable
AWS Direct Connect gateways per transit gateway 20 No
Transit gateways per AWS Direct Connect gateway 6 No

Maximum transmission unit (MTU)

  • The MTU of a network connection is the size, in bytes, of the largest permissible packet that can be passed over the connection. The larger the MTU of a connection, the more data that can be passed in a single packet. A transit gateway supports an MTU of 8500 bytes for traffic between VPCs, AWS Direct Connect, Transit Gateway Connect, and peering attachments (intra-Region, inter-Region, and Cloud WAN peering attachments). Traffic over VPN connections can have an MTU of 1500 bytes.

  • When migrating from VPC peering to use a transit gateway, an MTU size mismatch between VPC peering and the transit gateway might result in some asymmetric traffic packets dropping. Update both VPCs at the same time to avoid jumbo packets dropping due to a size mismatch.

  • Packets with a size larger than 8500 bytes that arrive at the transit gateway are dropped.

  • The transit gateway enforces Maximum Segment Size (MSS) clamping for all packets. For more information, see RFC879.

  • For details about Site-to-Site VPN quotas for MTU, see Maximum transmission unit (MTU) in the AWS Site-to-Site VPN User Guide.

  • Transit gateways support Path MTU Discovery (PMTUD) for traffic ingressing on VPC attachments. Transit gateway generates the FRAG_NEEDED for ICMPv4 packets and Packet Too Big (PTB) for ICMPv6 packets. Transit gateways does not support PMTUD on Connect, Site-to-site VPN, Direct Connect and Peering attachments. For more information about Path MTU Discovery, see Path MTU Discovery in the Amazon VPC User Guide

Multicast

Name Default Adjustable
Multicast domains per transit gateway 20 Yes
Multicast network interfaces per transit gateway 10,000 Yes
Multicast domain associations per VPC 20 Yes
Sources per transit gateway multicast group 1 Yes
Static and IGMPv2 multicast group members and sources per transit gateway 10,000 No
Static and IGMPv2 multicast group members per transit gateway multicast group 100 No
Maximum multicast throughput per flow 1 Gbps No
Maximum aggregate multicast throughput per Availability Zone 20 Gbps No

AWS Network Manager

Name Default Adjustable
Global networks per AWS account 5 Yes
Devices per global network 200 Yes
Links per global network 200 Yes
Sites per global network 200 Yes
Connections per global network 500 No

Additional quota resources

For more information, see the following: