L3 Port-channel restriction on ISR 4K?

[m1xed0s]

I remember a while back I saw a doc about following restriction in similiar wording about port-channel/etherchannel supportiveness on the ISR 4K.

"It is not supported to build an etherchannel with member ports from different modules."

I have a 4451-x running IOS-XE v17.6.5 with NIM-2GE-CU-SFP besides the front panel module. I want to build a port-channel/etherchannel with member ports from front panel module as well as the NIM...The system accepts the configuration without issue but I do not know if it would be functioning fine...

Also I can not find that doc to show me about this above restriction anymore and wondering if anyone could help advise if this is still valid restriction?

Thanks!

[MHM Cisco World]

ISP 4K is not support LACP so you need to make PO mode ON not active/passive 
check the interface status 
and check of the PO input/output count increase or not 

[m1xed0s]

Actually I disagree. I do have LACP port-channel running on ISR 4K and ASR routers. But I just don’t know about channel member ports from two network modules.

[Joseph W. Doherty]

"I do have LACP port-channel running on ISR 4K and ASR routers."

Yea, I thought I've read that.  BTW, however, definitely earlier ISRs, with also their earlier IOS versions, did not support LACP.  You had to manually activate Etherchannel, as @MHM Cisco World described.  Those platforms also didn't support any load balancing algorithm choices either.  Don't know if that's still true too.

Regarding different network modules, I recall on 6500s, there were issues using Etherchannel with ports on different line card architectures, although there was a command to override the restriction.  Perhaps there was (is) a similar restriction when mixing built-in ports vs. modular ports (vs. other modular ports), on later ISRs and/or ASR, for a similar reason, i.e. different port supporting hardware architectures under the covers.