On SRX Series Firewalls, the fabric data link does not support packet fragmentation. To handle this limitation, jumbo frame support is enabled by default on the fabric data link, with a maximum transmission unit (MTU) of 9014 bytes (9000 bytes payload + 14 bytes Ethernet header).

To ensure smooth traffic flow across the fabric, it is important that all participating interfaces are configured with an MTU that does not exceed the fabric data link MTU. Incorrect MTU settings can lead to dropped packets or communication issues.

SRX Series devices support jumbo frames up to 9192 bytes.

Jumbo frames are Ethernet frames with more than 1500 bytes of payload (maximum transmission unit [MTU]). Jumbo frames can carry up to 9000 bytes of payload.

To configure jumbo frames on SRX Series devices, you need to set the MTU (Maximum Transmission Unit) size on the physical interface. Jumbo frames are Ethernet frames with more than 1500 bytes of payload and can carry up to 9000 bytes of payload. However, on SRX Series devices, the maximum supported MTU size is 9192 bytes.

Here is how you can configure jumbo frames on an SRX device using the CLI:

1. Enter configuration mode:
2. root> configure
3. Set the MTU size on the desired interface (e.g., ge-0/0/0): set interfaces ge-0/0/0 mtu 9192
4. Commit the configuration: commit

This will configure the interface to support jumbo frames with an MTU size of up to 9192 bytes.

Example:root> configure

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root# set interfaces ge-0/0/0 mtu 9192

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root# commit