The details on what upgrade paths are supported are found in the release notes for the final target version, in your case 21.4, organized by platform, in your case EX.
https://www.juniper.net/documentation/us/en/software/junos/release-notes/21.4/junos-release-notes-21.4r3/topics/upgrade-downgrade/ex-upgrade-downgrade.html
Here you can see there is support for 3 major version jump, the first number in Junos version. So you can go directly from 18.1 to 21.4 on the ex4600.
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Steve Puluka BSEET - Juniper Ambassador
IP Architect - DQE Communications Pittsburgh, PA (Metro Ethernet & ISP - Retired)
http://puluka.com/home------------------------------
Original Message:
Sent: 07-05-2023 03:39
From: KARTHIKEYAN SHANMUGAM
Subject: Upgrade path for EX4600
3 device stack ...
current version - 18.1
Target version - 21.4
kindly let me know upgrade path or i can do 18.1 > 20.4 > 21.4
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KARTHIKEYAN SHANMUGAM
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