Fibre Channel (SAN)

Reply
Occasional Contributor
Posts: 19
Registered: ‎09-02-2013
Accepted Solution

Details needed for FPI

According to Brocade Monitoring and Alerting Policy Suite Configuration Guide, MAPS monitors the current latency on F_Ports over different time windows to determine the impact of latency on the fabric. If it determines the latencies on these ports are severe enough to significantly impact fabric performance, the state of that port is changed to  IO_PERF_IMPACT or IO_FRAME_LOSS, depending on the severity, and the state change is reported to the MAPS dashboard. When the latencies drop to normal levels, the port state is changed to IO_LATENCY_CLEAR. The IO_PERF_IMPACT value is calculated using buffer credit zero or transient queue latency counters, while IO_FRAME_LOSS is calculated using transient queue latency only.

For determining transient queue latency, MAPS has two predefined threshold states: IO_PERF_IMPACT and IO_FRAME_LOSS. the IO_PERF_IMPACT state is set for a port when latency is between the pre-defined low threshold and high threshold values. The IO_FRAME_LOSS state is set for a port when latency is greater than the pre-defined high threshold value.

My questions:

1. What are these different time zones ?
2. what are the pre-defined thresholds values (low and high) used for TXQ?
3. is pre-defined meaning it's defined in the FOS code, or are these configurable thresholds?

Brocade Moderator
Posts: 49
Registered: ‎04-27-2009

Re: Details needed for FPI

Hi there,

 

First of all I want to point out that TXQ Latency is for Condor3 with FOS 7.4 and above.

 

1. What are these different time zones ?

 

IO_PERF_IMPACT in FOS 7.3 is using 3 time windows to categorize the severeness or pattern of the latency:

30% tim_txcrd_z in 10 seconds

50% tim_txcrd_z in 5 seconds

70% tim_txcrd_z in 1 second


2. what are the pre-defined thresholds values (low and high) used for TXQ?

The low is 10ms

The high is 80ms


3. is pre-defined meaning it's defined in the FOS code, or are these configurable thresholds?

Pre-defined means its hard coded in FOS and not configurable

 

TL

Any and all information provided by me is not reviewed, approved or endorsed by Brocade and is provided solely as a convenience for Brocade customers. All systems and all networks are different and unique. If you have a service affecting network problem, please open a TAC service request for service through Brocade, or through your OEM equipment provider. If this provided you with a solution to this issue, please mark it with the button at the bottom "Accept as solution".
Occasional Contributor
Posts: 19
Registered: ‎09-02-2013

Re: Details needed for FPI

Hi Thomas,

 

Thanks a lot for your reply. I'm still strugling to get a good understanding of FPI and on when what portstatus is triggered.

I've tried to build a table indicating when, what port status is set. And I try to understand when and based upon what the port status is cleared.

 

Do you mind reviewing this table and help me to complete it? Please find it attached.

 

Many thanks and regards,

 

Jan C

 

 

Brocade Moderator
Posts: 49
Registered: ‎04-27-2009

Re: Details needed for FPI

Jan,

 

what is the FOS version you are running?

 

TL

Any and all information provided by me is not reviewed, approved or endorsed by Brocade and is provided solely as a convenience for Brocade customers. All systems and all networks are different and unique. If you have a service affecting network problem, please open a TAC service request for service through Brocade, or through your OEM equipment provider. If this provided you with a solution to this issue, please mark it with the button at the bottom "Accept as solution".
Occasional Contributor
Posts: 19
Registered: ‎09-02-2013

Re: Details needed for FPI

Hi Thomas,

 

 

We are running FOS v7.4.1c

 

Thanks and regards,

 

Jan C

Brocade Moderator
Posts: 49
Registered: ‎04-27-2009

Re: Details needed for FPI

Jan,

 

your document looks correct. I think the clear port states if avail. are simply when the condition isn't true anymore.

 

TL

Any and all information provided by me is not reviewed, approved or endorsed by Brocade and is provided solely as a convenience for Brocade customers. All systems and all networks are different and unique. If you have a service affecting network problem, please open a TAC service request for service through Brocade, or through your OEM equipment provider. If this provided you with a solution to this issue, please mark it with the button at the bottom "Accept as solution".
Occasional Contributor
Posts: 19
Registered: ‎09-02-2013

Re: Details needed for FPI

Thomas,

 

Thanks a lot for your support to get some understanding on how FPI works.

 

Regards,

 

Jan C

Join the Community

Get quick and easy access to valuable resource designed to help you manage your Brocade Network.