Quotas for your transit gateways - Amazon Virtual Private Cloud

Quotas for your transit gateways

Your AWS account has the following quotas (previously referred to as limits) related to transit gateways.

The Service Quotas console provides information about Network Manager quotas. 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
Transit gateways per VPC 5 No
CIDR blocks per transit gateway 5 No

The CIDR blocks are used in the Transit gateway Connect attachments and Transit Gateway Connect peers feature.

Routing

Name Default Adjustable
Transit gateway route tables per transit gateway 20 Yes
Routes per transit gateway 10,000 Yes
Dynamic routes advertised from a virtual router appliance to a Transit Gateway Connect peer 1,000 No
Routes advertised from a Transit Gateway 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 attachment to the same VPC.

Name Default Adjustable
Attachments per transit gateway 5,000 Yes
Unique transit gateway attachments 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 1 No
Transit Gateway Connect peers (GRE tunnels) per transit gateway 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.

Name Default Adjustable
Maximum bandwidth per VPC, AWS Direct Connect gateway, or peered transit gateway connection Up to 50 Gbps No
Maximum packets per second per transit gateway attachment (VPC, VPN, Direct Connect, and peering attachments) Up to 5,000,000 No
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 Transit Gateway 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 Transit Gateway 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 Transit Gateway 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 Transit Gateway 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 3 No

MTU

  • The maximum transmission unit (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, Direct Connect gateway, and peering attachments. Traffic over VPN connections can have an MTU of 1500 bytes.

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

  • The transit gateway does not generate the FRAG_NEEDED for ICMPv4 packet, or the Packet Too Big (PTB) for ICMPv6 packet. Therefore, the Path MTU Discovery (PMTUD) is not supported.

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

Multicast

Name Default Adjustable
Multicast domains per transit gateway 20 Yes
Multicast network interfaces per transit gateway 1,000 Yes

Members per transit gateway multicast group

100 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 4 Gbps No

Transit Gateway 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: