Edge-X S3 CRD

The API provides access to advanced EdgeFS Object interfaces, such as access to Key-Value store, S3 Object Append mode, S3 Object RW mode and S3 Object Stream Session (POSIX compatible) mode. A Stream Session encompasses a series of edits to one object made by one source that are saved as one or more versions during a specific finite time duration. A Stream Session must be isolated while it is open. That is, users working through this session will not see updates to this object from other sessions.Stream Session allows high-performance POSIX-style access to an object and thus it is beneficial for client applications to use HTTP/1.1 Persistent Connection extensions, to minimize latency between updates or reads.

For more detailes on API please refer to Edge-S3 API.

Rook allows creation and customization of Edge-X S3 services through the custom resource definitions (CRDs). The following settings are available for customization of Edge-S3 services.

Sample

apiVersion: edgefs.rook.io/v1
kind: S3X
metadata:
  name: s3x01
  namespace: rook-edgefs
spec:
  instances: 3
  #chunkCacheSize: 1Gi
  # A key/value list of annotations
  annotations:
  #  key: value
  placement:
  #  nodeAffinity:
  #    requiredDuringSchedulingIgnoredDuringExecution:
  #      nodeSelectorTerms:
  #      - matchExpressions:
  #        - key: role
  #          operator: In
  #          values:
  #          - s3x-node
  #  tolerations:
  #  - key: s3x-node
  #    operator: Exists
  #  podAffinity:
  #  podAntiAffinity:
  #resourceProfile: embedded
  resources:
  #  limits:
  #    cpu: "500m"
  #    memory: "1024Mi"
  #  requests:
  #    cpu: "500m"
  #    memory: "1024Mi"

Metadata

• name: The name of the Edge-X S3 system to create, which must match existing EdgeFS service.
• namespace: The namespace of the Rook cluster where the Edge-X S3 service is created.
• sslCertificateRef: If the certificate is not specified, SSL will use default crt and key files. If specified, this is the name of the Kubernetes secret that contains the SSL certificate to be used for secure connections. Please see secret YAML file example on how to setup Kuberenetes secret. Notice that base64 encoding is required.
• port: The port on which the Edge-X S3 pods and the Edge-X S3 service will be listening (not encrypted). Default port is 3000.
• securePort: The secure port on which Edge-X S3 pods will be listening. If not defined then default SSL certificates will be used. Default port is 3001.
• instances: The number of active Edge-X S3 service instances. For load balancing we recommend to use nginx and the like solutions.
• chunkCacheSize: Limit amount of memory allocated for dynamic chunk cache. By default S3X pod uses up to 75% of available memory as chunk caching area. This option can influence this allocation strategy.
• annotations: Key value pair list of annotations to add.
• placement: The Edge-X S3 PODs can be given standard Kubernetes placement restrictions with nodeAffinity, tolerations, podAffinity, and podAntiAffinity similar to placement defined for daemons configured by the cluster CRD.
• resourceProfile: S3X pod resource utilization profile (Memory and CPU). Can be embedded or performance (default). In case of performance an S3X pod trying to increase amount of internal I/O resources that results in higher performance at the cost of additional memory allocation and more CPU load. In embedded profile case, S3X pod gives preference to preserving memory over I/O and limiting chunk cache (see chunkCacheSize option). The performance profile is the default unless cluster wide embedded option is defined.
• resources: Set resource requests/limits for the Edge-X S3 Pod(s), see Resource Requirements/Limits.

Setting up EdgeFS namespace and tenant

For more detailed instructions please refer to EdgeFS Wiki.

Below is an exampmle procedure to get things initialized and configured.

Before new local namespace (or local site) can be used, it has to be initialized with FlexHash and special purpose root object.

FlexHash consists of dynamically discovered configuration and checkpoint of accepted distribution table. FlexHash is responsible for I/O direction and plays important role in dynamic load balancing logic. It defines so-called Negotiating Groups (typically across zoned 8-24 disks) and final table distribution across all the participating components, e.g. data nodes, service gateways and tools.

Root object holds system information and table of namespaces registered to a local site. Root object is always local and never shared between the sites.

To initialize system and prepare logical definitions, login to the toolbox as shown in this example:

kubectl get po --all-namespaces | grep edgefs-mgr
kubectl exec -it -n rook-edgefs rook-edgefs-mgr-6cb9598469-czr7p -- env COLUMNS=$COLUMNS LINES=$LINES TERM=linux toolbox

Assumption at this point is that nodes are all configured and can be seen via the following command:

efscli system status

1. Initialize cluster

Verify that HW (or better say emulated in this case) configuration look normal and accept it

efscli system init

At this point new dynamically discovered configuration checkpoint will be created at $NEDGE_HOME/var/run/flexhash-checkpoint.json This will also create system “root” object, holding Site’s Namespace. Namespace may consist of more then single region.

1. Create new local namespace (or we also call it “Region” or “Segment”)

efscli cluster create Hawaii

1. Create logical tenants of cluster namespace “Hawaii”, also buckets if needed

efscli tenant create Hawaii/Cola
efscli bucket create Hawaii/Cola/bk1
efscli tenant create Hawaii/Pepsi
efscli bucket create Hawaii/Pepsi/bk1

Now cluster is setup, services can be now created.

1. Create Edge-X S3 services objects for tenants

efscli service create s3x s3x-cola
efscli service serve s3x-cola Hawaii/Cola
efscli service create s3x s3x-pepsi
efscli service serve s3x-pepsi Hawaii/Pepsi

1. Create S3X CRDs

apiVersion: edgefs.rook.io/v1
kind: S3X
metadata:
  name: s3x-cola
  namespace: rook-edgefs
spec:
  instances: 1

apiVersion: edgefs.rook.io/v1
kind: S3X
metadata:
  name: s3x-pepsi
  namespace: rook-edgefs
spec:
  instances: 1

At this point two Edge-X S3 services should be available and listening on default ports.