Port saturation affect whole switch?

[n3tm1n]

Currently we have 2 E6600 48 port switches where a few of ports are configured for Storage device replication.

At times, I see the specific ports pegged out at 97 %. When these ports are saturated, does it affect the whole switch and the rest of the traffic flowing through the other ports. I am using PCM+ to monitor the traffic.

Reason, I'm asking is our company has a VoIP system (on seperate VLAN for the storage VLAN with the highest QOS) and often there is delay communicating with e-mail server in regards to our Voicemail greeting there's a noticable delay.  It seems when the switch ports are not saturated, there little delay.

Also, would limiting the bandwidth on the saturated ports help? If so, how would I go about doing so. Firmware is K14.47

Please advise

[Antonio Milanese]

Hello,

per specs the E6600 48G has 36MB QDR ram for packet buffers so nearly 750kb on per GbE, a decent amount  (since it's not shared) and generally out-of-buffer discards a rare case in situations of "normal" non storage traffic.

So I I would check "show cpu" and "show int" to see if it is the switch forwarding capacity really under attack.

Another questions is QoS applied to DATA/VOIP packtes? and if yes relative mapped queues are "starving" or oversubscribed ?

on E6600 since share 5400 codebase you've a following four pri queues/pkt buffers conf:

q1: pri 0-1  -> 8% buffers

q2: pri 0-1  -> 16% buffers

q3: pri 0-1  -> 30 % buffers

q4: pri 0-1  -> 45% buffers

Regards,

Antonio