This article covers known limitations and workarounds for the APM414 interface card series on the M4350-16M4V (MSM4320) switch, including link-up delays, hot-swap restrictions, TSC-F mode constraints, and interface card insertion requirements.
Limitation 1:
25G DAC link-up delay in back-to-back configurations (APM414V)
Due to APM414V chipset constraints, establishing a link between two MSM4320 units connected back-to-back through 25G DAC cables might take approximately 15 to 70 seconds on both ends.
Using higher-quality 25G DAC cables with lower routing impedance can help reduce link-up time.
There is no delay observed in the following configurations:
- Non-back-to-back configurations
- Use of AOC cables
- Use of 1 meter DAC cables
Limitation 2:
Hot-swap restrictions between 10G and 25G transceivers (APM414LD/APM414SD)
Hot-swapping is supported among the APM414V, APM414LD, APM414C, and APM414SD modules. Hot-swapping between different 10G and 25G transceivers within the APM414LD/SD is not currently supported.
Workaround: Restart the MSM4320 switch whenever the internal module speed changes from 25G to 10G.
Limitation 3:
10G and 25G cannot coexist on the same interface card (APM414LD/APM414SD)
APM414LD/SD operate in TSC-F mode. 10G and 25G speeds cannot coexist on the same interface card.
Limitation 4:
Driver crashes if you insert an interface card too soon
If you insert an interface card too soon after the previous insertion, it might cause an unexpected crash during driver initialization. Allow a minimum of 10 minutes between each interface card insertion.