I could be mistaken when I say this, but I believe that command should only be done on mgmt server, but maybe someone else can confirm. Btw, I get same on my R81.20 fw
[Expert@quantum-firewall:0]# cprid_util -server 172.15.10.205 getarch
unknown
[Expert@quantum-firewall:0]# cprid_util -server 172.15.10.203 getarch
unknown
[Expert@quantum-firewall:0]# cpinfo -y fw1
This is Check Point CPinfo Build 914000231 for GAIA
[FW1]
HOTFIX_PUBLIC_CLOUD_CA_BUNDLE_AUTOUPDATE
HOTFIX_GOT_TPCONF_AUTOUPDATE
FW1 build number:
This is Check Point's software version R81.20 - Build 703
kernel: R81.20 - Build 597
[Expert@quantum-firewall:0]#