Switching

Can anyone let me know the recommend upgrade version for ex4300-48t ex4300-48t  mx960 and why?

Hi Narasimha, 

I would always follow this official link:

Junos Software Versions - Suggested Releases to Consider and Evaluate

From Juniper's website:

which is currently up to v21.4R3-S12 issued 04 Dec 2025 available for download from

https://webdownload.juniper.net/swdl/dl/secure/site/1/record/190857.html?pf=EX4300

For MX960 with SCBE3 and MX960 with MPC10E it lists Latest Junos 24.4R2-Sx release. 

Hi,

Use this link to choose the correct JunOS version. It 's recomended by JTAC.

https://supportportal.juniper.net/s/article/Junos-Software-Versions-Suggested-Releases-to-Consider-and-Evaluate

as per all below recommendations

but yeah for the EX Junos 21.4R3-S12, there may be a later version on the 21.4

for the mx use 23.4R2 but check if you have routing Engines like RE-S-1800 or better 

For the MX: last supported JunOS with Routing Engines RE-S-1800 is 21.2. This RE will be End of Support (and actually End of All) within 2 months from now (and same thing for older SCBE, and MPCs like 16x10G, MPC2/MPC3 not-NG...).

Those days, with more modern hardware inside the chassis, you need either the older RE-S-X6-64G-S or the newer RE-S-X6-128G-S, with at least SCBE2.