N9K FC Connection - replace from 4GB to 16 GB SFPs without downtime

[robad]

Hi Team,

We have pair of Nexus9000 C93360YC-FX2 which are connected to Nimble Storage HF60   with 2 4GB FC connections from each Nexus to Each controller. (When we installed the Nexus, we tried to connect it with 8GB, but as per Cisco Bug, it's working only with 16 or 4 GB, and we had only 4GB).

Now, we purchased 16GB SFPs (ds-sfp-fc16g-sw)to upgrade to connections.

My question is, what is the best way to di it without a downtime ? If I'll replace from 4GB to 16GB one by one, will it work meanwhile, while the Nexus will have some ports to Nimble with 4GB and some with 16, few minutes until I'll complete to replace it all ?

Here is a draw :

thanks in advance !!!!

[robad]

** Of course there is a mistake on the draw, and the left Nexus is n9k-dc-A

[robad]

someone please ?

[advinski · Accepted solution]

Sure, replace one by one and check connectivity from initiator side

[robad]

@advinski  - Thanks a lot for your response !

[robad]

Hi,

The replacement was unsuccessful. I've opened a new thread on it :

https://community.cisco.com/t5/data-center-switches/nexus-9000-can-t-recognize-16gb-sfp/m-p/5110195#M9710

Thanks

[blogaccess07]

This is a great post. I like this topic. I found many interesting things from this site. Thanks for posting this again

[blogaccess07 · Accepted solution]

To upgrade the connections from 4GB to 16GB SFPs on your Nexus 9000 switches connected to Nimble Storage HF60 without incurring downtime, here is a step-by-step plan to ensure a smooth transition:

1. Preparation:

   • Ensure you have all necessary equipment and SFPs (ds-sfp-fc16g-sw) ready.
   • Verify that both the Nexus 9000 and Nimble Storage support hot-swappable SFPs and that the new SFPs are compatible.
   • Confirm that the Nimble Storage controllers are configured for redundancy and that each controller can handle the load during the upgrade process.

2. Redundancy Check:

   • Ensure that each Nimble Storage controller can handle the I/O load independently. This ensures that if one connection is temporarily lost, the other can handle the operations without disruption.

3. Upgrade Process:

   • Step 1: Start with one of the Nexus 9000 switches.
     • Identify the first 4GB SFP port to be replaced.
     • Disconnect the 4GB SFP and replace it with the 16GB SFP.
     • Reconnect the fiber cable to the new 16GB SFP.
     • Allow a few seconds for the new connection to be established and verified.
     • Monitor the network and storage performance to ensure there is no disruption.
     • Repeat the process for each 4GB SFP on the first switch.
   • Step 2: Move to the second Nexus 9000 switch.
     • Follow the same procedure as Step 1.
     • Replace each 4GB SFP with the 16GB SFP one at a time.
     • Ensure each new connection is stable before moving to the next.

4. Verification:

   • After all SFPs are replaced, monitor the network and storage systems to confirm that all connections are stable and operating at 16GB.
   • Verify the performance metrics to ensure there are no issues with data throughput or latency.

5. Testing:

   • Conduct thorough testing to ensure that all connections are functioning correctly and that there are no interruptions in service.
   • Check for any errors or alerts in the Nexus 9000 switches and Nimble Storage systems.

By replacing the SFPs one by one, you can maintain at least one active connection from each Nexus switch to each Nimble controller, ensuring continuous operation and minimizing the risk of downtime.

This method ensures that your system remains operational while upgrading to higher-speed connections, leveraging the redundancy built into your storage and network infrastructure. 

My account access

[robad]

Thanks for the detailed reply.

It seems to be the correct answer, but, see my message :

Hi,

The replacement was unsuccessful. I've opened a new thread on it :

https://community.cisco.com/t5/data-center-switches/nexus-9000-can-t-recognize-16gb-sfp/m-p/5110195#M9710