RE: Use case for running SPC2 and SPC3 card together in SRX 5800 cluster
2 weeks ago
The SPC3 card enables performance and scale with backwards compatibility to the SPC2 service cards but you might want to consider RE/CB compatibility as well. These SPC3 cards support in-service software and in-service hardware upgrades.
Refer Figure1: Interoperability Matrix for SRX5400, SRX5600, and SRX5800 Services Gateways
SRX5K-SPC3 card with flow support in chassis cluster mode (SRX5400, SRX5600, and SRX5800)—Starting in Junos OS Release 18.4R1, the SRX5K-SPC3 and SRX5K-SPC-4-15-320 (SPC2) cards can operate together in a mixed-mode configuration on the SRX5000 line of devices using the same slot number in both nodes. If you are adding the SPC3 SPCs to the SRX5000 devices, you must install the new SPCs in the lowest-numbered slot of any SPC that provides central point functionality. SPC3 interoperates with the SRX5000 I/O cards (IOC2, IOC3), Switch Control Boards (SCB2, SCB3), Routing Engines, and SPC2 cards.
For an SPC3/SPC2 Mixed Mode, CP is always in SPC3. SPC3 needs to be installed in the lower number slots (starting the first slot) as you have mentioned. Also, system assigns cores to CP and SPU based on the number of SPC2/SPC3 in the chassis. CP will work on combo mode if there are 1 or 2 SPC3 cards, and CP will work on full CP mode if there are 3+ SPC3 cards, it doesn’t count SPC2 cards number. In certain combinations sometimes, the total session capacity could be reduced, comparing to pure SPC2 mode. It is recommended to have at least 2 SPC3 cards when running with SPC3 + SPC2 mixed mode to maintain/increase session capacity.
My recommendation is to either fill-up all slots with SPC2 for better performance or replace the SPC2 cars, if possible.
_ Regards Malik JNCIEx4, CCIE, HCIE, VCIX-DCV, VCIX-NV, CISSP, PMP
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