Both voip abd data have static it's.
All Ports are configured as tag for voice and untag for data.
Some pc's and printers are directly connected to switch ports (not through phones) and have static IP configured from data vlan.
Is there any possibility of above causing few phones to hang....?
No issue with VoIP and data on the same port or having VoIP tagged. That is the proper config. I would move the phones to other ports, maybe ones that have phones that are connected and not seeing the issue. If you swap them and it follows the phone then that should be a key indicator. If it stays with the port then it can point to the cable.
You can also do a show port info on those ports and see if the up/down counters are going up showing a port disconnect or is it just the phones not responding.
I have a similar issue with an active GTAC case open. GTAC has reviewed my DHCP bootprelay configuration and routing.
Environment: X450-G2 Summit with 188.8.131.52 code
Scenario: Data untagged, voice tagged. A Siemens Unify phone will randomly not obtain an IP from VLAN ID discovery through DHCP. Doesn't matter which switchport. We have 802.1x and MAC auth enabled. Disabling MAC authentication on the port seems to always allow the phone to complete its DHCP discovery process. When a phone does not pull an IP, the MAC is not learned in the voice vlan.
I have found 3 ways to get the phone to work in the meantime 1) Disable netlogin mac on the port 2) Run a disable port x followed by enable port x commands 3) Move the phone to a different switchport.
Disabling inline-power to the switchport, physically unplugging the phone and plugging it back in, replacing the phone with a new phone, replacing the patch cable all have no affect. DHCP PCs (using untagged data vlan) using the phone's pass through work fine all of the time.
We run the same configuration on many K-Series, S-Series, N-Series and have no issues with Unify phones.