Why do we always see Responder CQE Errors with RoCE RDMA?

Anyone who has configured and used SMB Direct with RoCE RDMA Mellanox cards appreciates the excellent diagnostic counters Mellanox provides for use with Windows Performance Monitor. They are instrumental when it comes to finding issues and verifying everything is working correctly.

Many have complained about the complexity of DCB configuration but in all earnest, any large network under congestion which needs specialized configurations has challenges due to scale. This is no different for DCB. You need the will to tackle the job at hand and do it right. Doing anything at scale reliable and consistent means automating it.  Lossless Ethernet, mandatory or not, requires DCB to shine. There is little other choice today until networking technology & newer hardware solutions take an evolutionary step forward. I hope to address this in a future article. But, this I not what we are going to discuss here. We’ve moved beyond that challenge. We’ll talk about one of the issues that confuse a lot of people.

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NIC teaming is not something we got with Windows Server 2016 but I just find it interesting to review this functionality as we have it in the current iteration of Windows Server, as usual, touching a bit on basics and history of this feature.

NIC teaming feature reached its maturity in Server 2012 R2 and there are (almost) no major changes in this department in Server 2016, yet if you just starting out with a practical use of NIC teaming on prepping for any related Microsoft exam you may find it useful to review this feature thoroughly.

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I’ve been using VMWare’s VPID (Virtual Port ID) technology for some time now both in work and in the home lab but I was curious to see just how VMWare handled a NIC going down and then coming back up and it turned out to be a lot more powerful and smooth than I first though.

In my lab, I’ve got several HP Microservers and a mix of TP-Link and Netgear switches.
I’ve found the TP-Link switches to be perfect for a lab as they have 48 1GBit ports and 4 1GBit FC ports. They haven’t cheapened out like Netgear have with the link between the last two Ethernet and the first two FC. With Netgear, you can only use last two Ethernet OR the first two FC ports.
You cannot use all of the ports on the switch. With TP-Link, all the ports are available and I find the web GUI a little more initiative although I did experience a bug on the TP-Link where the SNMP Engine kept crashing. This was fixed in a firmware upgrade so it wasn’t a major issue.

Anyway back to VMWare and VPID!

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The placement of the virtual machines in a Hyper-V cluster is an important step to ensure performance and high availability. To make a highly available application, usually, a cluster is deployed spread across two or more virtual machines. In case of a Hyper-V node is crashing, the application must keep working.

But the VM placement concerns also its storage and its network. Let’s think about a storage solution where you have several LUNs (or Storage Spaces) according to a service level. Maybe you have an LUN with HDD in RAID 6 and another in RAID 1 with SSD. You don’t want that the VM which requires intensive IO was placed on HDD LUN.

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Yesterday I saw a blog post in Homelab subreddit discussing what Intel NUC to choose. I have spent quite some time recently to choose the right server for my homelab expansion and I have considered a lot of options.

I was also looking at Intel  NUC as many other fellow IT professionals, but luckily last month I read on Tinkertry.com that Supermicro had just released new Mini-1U SuperServers – SYS-E300-8D and SYS-E200-8D.  I had some discussions with my colleagues and other people on Reddit and TinkerTry and I came to the conclusion that if you are aimed to run home lab for virtualization Intel NUC shouldn’t be considered. I believe SuperMicro is a new king on the market of mini servers for home lab.

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vSphere Replication has proved to be a great bonus to any paid vSphere license. It is an amazing and simple tool that provides cheap and semi-automated Disaster Recovery solution. Another great use case for vSphere Replication is migration of virtual machines.

vSphere Replication 6.x came with plenty of new useful features:

• Network traffic compression to reduce replication time and bandwidth consumption
• Linux guest OS quiescing
• Increase in scalability – one VRA server can replicate up to 2000 virtual machines
• Replication Traffic isolation – that is what we are going to talk today.

The goal of traffic separation is to enhance network performance by ensuring the replication traffic does not impact other business critical traffic. This can be done either by using VDS Network Input Output Control to set limits or shares for outgoing or incoming replication traffic. Another benefit of traffic isolation addresses security concern of mixing sensitive replication traffic with other traffic types.

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When a large Hyper-V infrastructure is deployed, often Virtual Machine Manager (VMM) is installed. It enables to deploy logical switches which are mainly VM Switches and virtual network adapters for Live-Migration, Backup, heartbeat, storage or management purposes. However small or medium business doesn’t necessarily implement VMM because it is expensive or not well-known. Even if you don’t use VMM, you can deploy consistency VM Switches on several Hyper-V by using PowerShell. This topic aims to show you how to deploy VM Switches and virtual network adapters by using PowerShell. In this way you will be able to make a standard script to configure your Hyper-V hosts.

Manage a teaming

The teaming may be necessary if you want a highly available environment

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