Ip assignment latency

[saborbas]

Hi

I am in need of assistance, Lately I have been noticing a delay when assigning IP address to the PC and laptops on my LAN. The problem might have always been there from the start but since I upgraded all the Pc/laptops on the network to SSD, boot time have been cut to under 10 seconds.  Here is the situation. 

IP assignment from my DHCP server takes about 90 Seconds. HD boot about 3min never noticed, SSD boot 10 seconds now we must wait 90 seconds for the IP assignment.  I've upgraded all firmwares (PC/Switch/Router) to the latest versions.

PC are dell OptiPlex, Laptops are Dell Latitudes. All are various models. Router ( DHCP server) is a Sonicwall Tz500, Switches are Cisco SG220's. 

If I bypass a switch and jacked directly to the back of the SonicWALL firewall, IP assignment is immediate. Same pc jacked via the cisco switch to Sonicwall, IP assignment take 90+seconds.  Switches/PC are setup with a vanilla config. No Jumbo packets, 

Appreciate any help

Sandor

[Reza Sharifi]

Hi,

Not familiar with SG series switches but make sure you enable portfast on access ports. Also, check to make sure the spanning tree protocol you are running is the same across all switches.

HTH

[saborbas]

Don't see portfast anywhere, Spanning Tree set as follows

Spanning Tree Enabled

Operations mode -Classic STP

BPDU handling- Flooding

Path Cost - Long

Priority - Default

Hello Time - Default

Max Age- Default

Forward Time- Default

Any help appreciated

[Reza Sharifi]

here is the config guide on how to enable it:

https://www.cisco.com/c/dam/en/us/td/docs/switches/lan/csbss/sf220_sg220/command_line_reference/Sx220_CLI_Guide.pdf

The following example enables the PortFast mode on gi15:
switchxxxxxx(config)# interface gi15
switchxxxxxx(config-if)# spanning-tree portfast

HTH

[marce1000]

 - Check the solving reply from this thread , it looks somewhat 'compatible' and or related to the fact that your PC's are booting much faster now :

        https://community.cisco.com/t5/switching/take-too-much-time-to-get-an-ip-over-a-cisco-switch/td-p/2895550

 M.