When your vSphere host does not display SANs correctly, you are required to use different troubleshooting techniques to make it work correctly.
It may happen that you are not able to find a port. This could be because of a disconnected network cable. Ensure that your cables are connected correctly; your link is up if you are able to find a green color link light else, replace the cable.
If your routes are not published correctly, you will have connectivity issues among different subnets of your LAN segments. Ensure your storage segment is accessible to the vSphere host's segments and correct routes are published between the subnets. Verify your settings of gateway address, IP address and subnet mask on SAN as well as in your vSphere hosts.
As mentioned previously, for iSCSI-based SANs, make sure the CHAP settings and the secret are correct. For iSCSI and NFS, make sure the access list allows your vSphere hosts to access the storage. For iSCSI and NFS clients' access, also...