This article talks about the issue observed with 'gre-performance-acceleration' knob on SRX devices.

+ You are using selective packet mode for MPLS traffic on SRX345 and using GRE over IPSEC over MPLS setup.

+ You have enabled 'gre-performance-acceleration' knob for GRE performance improvement

+ The end-to-end connectivity is broken.

+ This issue is observed on all SRX platforms when the "gre-performance-acceleration" knob is enabled. In label swap scenarios such as MPLSoGRE, the device fails to forward MPLS traffic, resulting in complete traffic loss. Disabling the knob restores packet forwarding functionality and resolves the issue.

+ This issue is fixed in PR1876356. The fix will be available in Junos:24.4R2 and Junos:25.3R1

+ Currently, the workaround is to disable the knob 'gre-performance-acceleration' on the Branch devices if you are using MPLS over GRE.

2025-04-12 : Article Created

2026-06-03: changed the article visibility