Here we were bitten by PR1813536.
In this PR, packets going through irb interfaces are eaten if bigger than 1496 bytes and toward/from interfaces with 1500 bytes of L3 MTU...
Those added 4 bytes might be the actual symptom of it.
It is fixed in 22.4R3-S5/S6 and 23.2R2-S2... but not in 23.4R2 [-S1/S2/S3]).
Maybe it's the PR you're experiencing, may it has nothing to do, but you should give a try the the mentioned versions.
We currently have a ticket opened with JTAC about the fix not (yet) implemented in 23.4 releases...
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Olivier Benghozi
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Original Message:
Sent: 02-05-2025 13:16
From: krazyblu
Subject: SRX1500 23.4R2.13 extra data added to packets/frames
The packet is going through an irb. The previous JUNOS version was: 21.2R3-S3.5
Original Message:
Sent: 02-05-2025 09:04
From: Olivier Benghozi
Subject: SRX1500 23.4R2.13 extra data added to packets/frames
Is it a packet going through an irb interface ?
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Olivier Benghozi
Original Message:
Sent: 02-04-2025 02:01
From: krazyblu
Subject: SRX1500 23.4R2.13 extra data added to packets/frames
Upgraded an SRX1500 to 23.4R2.13. We are seeing 4 bytes of extra data (all zeros) added to the end of packets forwarded by the srx1500. Has anyone seen this or can explain what is going on?
