If you are working with Brocade respectively Broadcom Fibre Channel (FC) switches, you have probably had similar experiences as I have. Normally switches are running without any issues after setup. Sometimes firmware needs to be updated and zoning needs to be extended. Otherwise they just run. Last week I had the opposite experience. I saw very strange behavior caused by a full root partition on […]
These days I had to troubleshoot poor VMware vSphere SAN transport mode performance during backup with Veeam. Before SAN mode, NDB transport mode was used. NBD outperformed SAN mode totally!
These days I had to troubleshoot a problem with system time within a VMware vSphere VM. During backup VM freezes for more than 30 seconds. When this happens, system time in VM also stops and resets to current time after the freeze. And this behavior causes massive problems in the application-layer. During troubleshooting we found a very slow VM snapshot deletion on NFS volumes on […]
I was troubleshooting storage related problems at a customer site for some time. We run into massive ESXi storage connection problems after installing a new array. Interestingly enough problems occurred on already existing storage a few hours after new array was installed. Because searching for root cause took some time, I thought it is worth to share.
Recently we had to troubleshoot rather high storage latency at a customer site. The environment consists of Hyper-V hosts connecting to 3PAR arrays via iSCSI. 3PAR arrays are all-flash arrays (AFA). I know such problems in vSphere environments too. There higher storage latency can be caused by delayed acknowledgement (DelAck). Read more about this issue and how to configure DelAck on vSphere ESXi hosts here. […]
A new – and badly documented – feature in StoreServ Management Console 3.6 is Topology Insights. Sounds first like the probably known Maps. But Topology View shows an end-to-end view: VM <–> VMDK <–> Datastore <–> Host <–> Virtual Volume <–> System. Enriched with performance-information! This short post is about this feature and how to get it.
First, what does active/standby mean. For this blog post, it means the array hast at least 2 controllers, one presents ALL LUNs to the hosts, the second controller presents NO active LUNs path to the hosts. Just in case of a manual or automatic failover, the second controller takes-over ALL LUN-presentations – and active paths. Examples of such arrays are: [very old one] HP MSA 1000 HPE Nimble […]
Normally when using a self-signed certificate you get a warning. It is also normal to accept the certificate to continue your task. These days I wanted to register a 3PAR system as storage provider in vCenter. Because of a certification error, this could not be accomplished. In this post I describe how to solve – at least my – problem.
Recently I had problems to connect a 3PAR system to a quorum appliance. Quorum is needed in a Peer Persistence configuration. The system had a connection to the quorum. After HPE support did replace a node, connection could not be established any more. Command showcropy -qw shows error “below min safe num QAs” and other errors talking about QAs. In SSMC quorum was stated as […]
The code snippet in this blog post is an example of how to add iSCSI targets to an ESXi iSCSI initiator. But there is also a loop within processing a host, that sets iSCSI target parameter. For example this can be used when a storage vendor recommends to disable delayed acknowledgment per iSCSI target, like HPE does for 3PAR and LeftHand. Here you can see […]