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Comment by philip1209 | Hacker News Reader

NFS in a modern system seems like a huge red flag.

What's wrong with NFS? If you need a shared, POSIX-compliant drive between multiple hosts, there's not really an alternative. Even the fairly new AWS Elastic File System service is just a NFS4.1-based managed service

While the grandparent comment might be a little too emphatic, surrendering the flexibility of file stores in favour of object stores does lend itself to permitting nice non-functional properties.

You can pay money for a SAN, which is $$$$ & enterprise but is a viable alternative…

A SAN gives you block storage - virtual hard disks. You will need a cluster filesystem to be able to use the same virtual disks on multiple machines concurrently, which are not easy to operate and have their own bunch of performance problems.

Some of the file systems come with native clients. I'd say for container environments that's a viable alternative to NFS. When done properly the native client can do low latency as it usually has the minimum number of network hops and do failover without requiring things like virtual IPs.

Speaking as someone who has maintained some rather large NFS utilizing systems/datacenters in the last decade, and found it perfectly suitable to my needs, I'd be curious to why you'd say that?

Not a block device, so not having cgroups (read/write bps limiting + iops limiting) is one annoyance of NFS in large deployments

I'd also add extreme fault intolerance. Even when you're mounting soft, or hard+intr, NFS failures have a way of requiring reboots to fully fix.

The intr mount option has been a no-op for 8 years.

/bin/umount does an fstat before the umount syscall, so if an NFS mount is broken, it will probably hang forever instead of unmounting it! You can invoke the syscall directly to get the behavior you need.

That hasn't been dependable in my experience - the best workaround I've found is either a lazy unmount + remount if you can tolerate the hung process taking the full NFS retry timeout to unblock or downing the network interface to accelerate the process.

This is fair to a degree, but vendors have VIPs that make failures fairly transparent. But if you need low latency on a large data set is there something better? Where low latency means <100ma reads

So use Jails, ZFS and rctl. Problem solved.

How does that fix a client accessing network storage?

You can use Samba with it. Unless you absolutely require NFS, samba is far more robust and less prone to needing to be hard rebooted.

I'd agree, it's hard to beat if you need high bandwidth and low latency access to large data sets.

throwing away 30+ years of protocol development for the latest and greatest containerization paradigm is what the cool kids south of market street talk about at happy hour.

If you want volumes that can be dynamically attached to any machine, you're not buying a SAN, and you're not in a cloud provider with a portable block storage abstraction, what do you propose?

About the only thing I can think of is Ceph, and it stands to reason there is a lot more NFS than Ceph expertise on the job market.

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