Smaller sites that would benefit from a cluster of 2-5 nodes. Not saying that it can't scale above that, but I find HyperFlex a great solution for those sites. A simple 3-node edge cluster can provide a huge amount of resources and redundancy. It's also really easy to scale the environment to meet growth requirements.
GFS is well suited for DEVOPS type environments where organizations prefer to invest in servers and DAS (direct attached storage) versus purchasing storage solutions/appliances. GFS allows organizations to scale their storage capacity at a fraction of the price using DAS HDDs versus committing to purchase licenses and hardware from a dedicated storage manufacturer (e.g. NetApp, Dell/EMC, HP, etc.).
UCS manager in HX is truly helping us in doing one touch firmware upgrades. Scaling of HX cluster (in few minutes) is too seamlessly due to service profiles.
HX does not hold you back by creating a single data store unlike other HCI products. With HX, you can create multiple data stores and allocate those to desired services. This help logically separate the install base on HX and removes confusion for the admins too.
We run high IOPs workload on HX, and we never felt latency issues due to the Cisco backbone (as you get FI as a TOR switch and options to choose 10G or 40G speeds).
With HX you truly enjoy a single window support from Cisco including for the top of the rack switch (FI in HX case). In other HCI infra, you certainly have to bank on to network switch vendor for support and bring HCI and switch vendor at one pane for troubleshooting latency related issues.
While we increased our footprint on HX, we didn't added additional administrators to support the landscape. This was possible because of the simplicity in managing HX clusters.
With HX we had setup stretched cluster between two near site data centres. This is a unique proposition in HX (we have 2 nodes in each data centre) and data centre failover works absolutely seamless.
Scales; bricks can be easily added to increase storage capacity
Performs; I/O is spread across multiple spindles (HDDs), thereby increasing read and write performance
Integrates well with RHEL/CentOS 7; if your organization is using RHEL 7, Gluster (GFS) integrates extremely well with that baseline, especially since it's come under the Red Hat portfolio of tools.
there is the problem with starting cluster where there are not outside DNS and NTP services so we need to workaround this with additional storage or hosting it on the local storage.. many clusters has internal DNS/NTP services not available from outside and they need to be hosted on the HX
there is not RBAC or user mgmt on the CVMs so it is difficult to not add full permission for the people responsible for just shutdown and power on the cluster
native snapshots support with ibm backup products
running from not the only last snapshot in all use cases
Documentation; using readthedocs demonstrates that the Gluster project isn't always kept up-to-date as far as documentation is concerned. Many of the guides are for previous versions of the product and can be cumbersome to follow at times.
Self-healing; our use of GFS required the administrator to trigger an auto-heal operation manually whenever bricks were added/removed from the pool. This would be a great feature to incorporate using autonomous self-healing whenever a brick is added/removed from the pool.
Performance metrics are scarce; our team received feedback that online RDBMS transactions did not perform well on distributed file systems (such as GFS), however this could not be substantiated via any online research or white papers.
More documentation is available now than when the product initially came out (which was an issue early on). Because it only supports UCS hardware, I think it does help with support issues. Nutanix has to support much more hardware. At the same time, you're dealing with the Cisco TAC, which can be mixed at times.
HyperFlex is built on top of Cisco UCS infrastructure, which allows us to manage other non-HX servers attached to the same UCS environment. This allows us to tie everything together via Intersight and see all of the servers in our data centers. Other platforms don't really have a comparable offering.
Gluster is a lot lower cost than the storage industry leaders. However, NetApp and Dell/EMC's product documentation is (IMHO) more mature and hardened against usage in operational scenarios and environments. Using Gluster avoids "vendor lock-in" from the perspective on now having to purchase dedicated hardware and licenses to run it. Albeit, should an organization choose to pay for support for Gluster, they would be paying licensing costs to Red Hat instead of NetApp, Dell, EMC, HP, or VMware. It could be assumed, however, that if an organization wanted to use Gluster, that they were already a Linux shop and potentially already paying Red Hat or Canonical (Debian) for product support, thereby the use of GFS would be a nominal cost adder from a maintenance/training perspective.
The simplified management makes it easier to operate and prevents mistakes.
Guided installation using the installer VM means you don't have to configure every component by hand. Improves deployment speed and lowers the risk of configuration issues.
Performance increase of 40-90% compared to our previous compute/storage cluster.
