To identify the problem collect SNMP walk of the device.
You can use sapwalk2.exe utility to collect SNMP walk. If you are running 10.2 or later the utility executable is in $SPECROOT/bin directory on the SpectroSERVER machine.
If you are running older Spectrum version, this utility can be downloaded via ftp from ftp.ca.com in the /pub/CA-SPECTRUM/Tools/sapwalk2 directory. You can login as anonymous user with your email address as password to the ftp server.
The usage can be found by just running the sapwalk2 executable. However, a recommended usage is as follows:
sapwalk2.exe -i <ip address> -v <snmp version> -s <starting oid> -p <port> -c <community name> -t <timeout> -r <retries> -d <throttle_delay> -o <outputfile>.walk
For example:
If device is discovered using SNMP v1:
sapwalk2.exe -i xx.xx.xx.xx -v v1 -s 1.3.6. -c public -t 3000 -r 3 -d 50 -o device_mib.walk
If device is discovered using SNMP v2:
sapwalk2.exe -i xx.xx.xx.xx -v v2c -s 1.3.6. -c public -t 3000 -r 3 -d 50 -o device_mib.walk
If device is discovered using SNMP v3:
sapwalk2.exe -i xx.xx.xx.xx -v v3 -s 1.3.6. -u xxxxx -l AP -xt MD5 -xa xxxxx -xp xxxxx -t 3000 -r 5 -o device_mib.walk
Open generated SNMP walk file, e.g. device_mib.walk, using text editor and search for 1.3.6.1.2.1.2.2.1 OID. If you don't have it this means device's MIB database doesn't have interface table information and Spectrum won't be able to model interfaces.
You should work with device's Administrator or Vendor to configure or implement interface table in the MIB database.