Table of Contents

Feature flags

Feature flags is a 64-bit (bit-wise) field in aistore cluster configuration denoting assorted (named) capabilities that can be individually enabled at runtime.

The features themselves are enumerated below. Not all feature flags - henceforth, “features” - are cluster-global.

Assorted features, denoted by (*) below, can also be changed on a per-bucket basis.

By default, all features are disabled, and the corresponding 64-bit field is set to zero.

Names and comments

name comment
Enforce-IntraCluster-Access when enabled, aistore targets will make sure not to execute direct (ie., not redirected) API calls
S3-API-via-Root handle S3 requests via aistore-hostname/ (whereby the default: aistore-hostname/s3)
Do-not-Allow-Passing-FQN-to-ETL do not allow passing fully-qualified name of a locally stored object to (local) ETL containers
Fsync-PUT(*) PUT and cold-GET: commit (or sync) the object payload to stable storage
Ignore-LimitedCoexistence-Conflicts run in presence of “limited coexistence” type conflicts
Skip-Loading-VersionChecksum-MD(*) skip loading existing object’s metadata, Version and Checksum (VC) in particular
LZ4-Block-1MB .tar.lz4 format, lz4 compression: maximum uncompressed block size=1MB (default: 256K)
LZ4-Frame-Checksum checksum lz4 frames
Do-not-Auto-Detect-FileShare do not auto-detect file share (NFS, SMB) when promoting shared files to AIS
S3-Presigned-Request(*) pass-through client-signed (presigned) S3 requests for subsequent authentication by S3
Do-not-Optimize-Listing-Virtual-Dirs when prefix doesn’t end with ‘/’ and is a subdirectory: don’t assume there are no prefixed object names (as in: a/subdir/obj1, a/subdir/obj2, but also a/subdir-obj3)
Disable-Cold-GET do not perform cold GET request when using remote bucket
S3-Reverse-Proxy use reverse proxy calls instead of HTTP-redirect for S3 API
S3-Use-Path-Style use older path-style addressing (as opposed to virtual-hosted style), e.g., https://s3.amazonaws.com/BUCKET/KEY
Do-not-Delete-When-Rebalancing when objects get rebalanced to their proper locations, do not delete their respective misplaced sources
Do-not-Set-Control-Plane-ToS intra-cluster control plane: do not set IPv4 ToS field (to low-latency)
Trust-Crypto-Safe-Checksums when checking whether objects are identical trust only cryptographically secure checksums

Global features

$ ais config cluster features <TAB-TAB>

Enforce-IntraCluster-Access            LZ4-Block-1MB                          Do-not-Optimize-Listing-Virtual-Dirs   Do-not-Delete-When-Rebalancing
Skip-Loading-VersionChecksum-MD        LZ4-Frame-Checksum                     Disable-Cold-GET                       Do-not-Set-Control-Plane-ToS
Do-not-Auto-Detect-FileShare           Do-not-Allow-Passing-FQN-to-ETL        Streaming-Cold-GET                     none
S3-API-via-Root                        Ignore-LimitedCoexistence-Conflicts    S3-Reverse-Proxy
Fsync-PUT                              S3-Presigned-Request                   S3-Use-Path-Style

For example:

$ ais config cluster features S3-API-via-Root Skip-Loading-VersionChecksum-MD Ignore-LimitedCoexistence-Conflicts
PROPERTY         VALUE
features         S3-API-via-Root,Ignore-LimitedCoexistence-Conflicts,Skip-Loading-VersionChecksum-MD

Cluster config updated

Tip: to select multiple features, type the first letter (or the few first letters) of the one you select, press <TAB-TAB> to complete, and then press <TAB-TAB> again to keep going, if need be.

To view the current (configured) setting, type the same command and hit Enter:

$ ais config cluster features
PROPERTY         VALUE
features         S3-API-via-Root,Ignore-LimitedCoexistence-Conflicts,Skip-Loading-VersionChecksum-MD

The same in JSON:

$ ais config cluster features --json
{
    "features": "1552"
}

Finally, to reset feature flags back to the system defaults, <TAB-TAB> to select none from the completion list, or simply run:

$ ais config cluster features none

PROPERTY         VALUE
features         none

Cluster config updated

Bucket features

By default, created and added (ie., discovered upon remote lookup) buckets inherit their properties from the cluster.

For background and details, see Default Bucket Properties.

It is possible, however, to change the defaults both at bucket creation time and/or at any later time.

Here’s a brief 1-2-3 demonstration in re specifically: feature flags.

## 1. show existing bucket-scope features:

$ ais bucket props set ais://nnn features <TAB-TAB>
Skip-Loading-VersionChecksum-MD   Fsync-PUT        S3-Presigned-Request       none

## 2. select and set:

$ ais bucket props set ais://nnn features S3-Presigned-Request
"features" set to: "512" (was: "0")

Bucket props successfully updated.
$ ais bucket props set ais://nnn features
PROPERTY         VALUE
features         512

## 3. reset feature flags back to zero (or 'none'):

$ ais bucket props set ais://nnn features none
"features" set to: "0" (was: "512")

Bucket props successfully updated.
$ ais bucket props set ais://nnn features
PROPERTY         VALUE
features         0