Tuesday, 7 January 2025

44. Env variables

ENV variables can be defined under ENV

Other ways to define ENV variables

config-map - Value is taken from outside
Secrets - Value is taken from outside.

ConfigMaps

When there are too many ENV files then it is better to define all variables in a seperate file in KEY/VALUE format.

How to create config-maps ( 2 ways )

- imperative and declarative.

Imperative way to create config-map

Declarative way for config-map

View Configmap

Config map in yaml file

Different ways of config-map

37. Define, Build and Modify Container Images.

Why ?

Created one application and we want to dockerize the application.

What are the steps if we have to deploy our application manually ?

- Deploy OS

- Update apt repo

- Install dependency using apt

- Install python dependency using pip

- Copy source folder to /opt

- Run web server using flask command.

Docker file with file name = <file-name>

FROM Ubuntu [FROM -> Instruction, Ubuntu->Argument] <---- Install OS

RUN apt-get update <------------ Install Dependencies

RUN apt-get install python

RUN pip install flask

RUN pip install flask-mysql

COPY . /opt/source-code <--- Copy source Code.

ENTRYPOINT FLASK_APP=/opt/source-code/app.py flask run <-- Specify Entry Point.

Build docker

docker build <docker-file> -t <TAG>

PUSH Docker

docker push <TAG>

38. Command and Arguments in Docker ( CMD, ENTRYPOINT )

40. Command and Argument in K8

Registration Request ( PCAP ) & 5G Index link

December 15, 2024 No comments

Registration request

5G | ShareTechnote

https://www.sharetechnote.com/html/5G/5G_Registration.html#Case_A_NormalRegistration

PDF : https://www.eventhelix.com/5G/standalone-access-registration/details/5g-standalone-access-registration.pdf

PDF : https://www.eventhelix.com/5G/standalone-access-registration/5g-standalone-access-registration.pdf

Spec Details : https://www.sharetechnote.com/html/5G/5G_RadioProtocolStackArchitecture.html

RedCap : https://www.sharetechnote.com/html/5G/Handbook_5G_Index.html

5G Index for Share Note : https://www.sharetechnote.com/html/5G/Handbook_5G_Index.html

NGAP Message

NG Application Protocol (InitialUEMessage)

NGAP-PDU: initiatingMessage (0)

initiatingMessage

procedureCode: id-InitialUEMessage (15)

criticality: ignore (1)

value

InitialUEMessage

protocolIEs: 5 items

Item 0: id-RAN-UE-NGAP-ID

ProtocolIE-Field

id: id-RAN-UE-NGAP-ID (85)

criticality: reject (0)

value

RAN-UE-NGAP-ID: 2768240640

Item 1: id-NAS-PDU

ProtocolIE-Field

id: id-NAS-PDU (38)

criticality: reject (0)

value

NAS-PDU: 7e004179000d0164f0110fff000000000000102e04f0f0e0e02b0100

Non-Access-Stratum 5GS (NAS)PDU

Plain NAS 5GS Message

Extended protocol discriminator: 5G mobility management messages (126)

0000 .... = Spare Half Octet: 0

.... 0000 = Security header type: Plain NAS message, not security protected (0)

Message type: Registration request (0x41) <-- Type of message ( If NAS_5GS_MSG_REGISTRATION_REQ then TMSI allocation is done

5GS registration type

.... 1... = Follow-On Request bit (FOR): Follow-on request pending

.... .001 = 5GS registration type: initial registration (1)

NAS key set identifier

0... .... = Type of security context flag (TSC): Native security context (for KSIAMF)

.111 .... = NAS key set identifier: 7

5GS mobile identity

Length: 13

0... .... = Spare: 0

.000 .... = SUPI format: IMSI (0)

.... 0... = Spare: 0

.... .001 = Type of identity: SUCI (1)

Mobile Country Code (MCC): China (460)

Mobile Network Code (MNC): Unknown (11)

Routing indicator: ?0

.... 0000 = Protection scheme Id: NULL scheme (0)

Home network public key identifier: 0

MSIN: 0000000001

UE security capability

Element ID: 0x2e

Length: 4

1... .... = 5G-EA0: Supported

.1.. .... = 128-5G-EA1: Supported

..1. .... = 128-5G-EA2: Supported

...1 .... = 128-5G-EA3: Supported

.... 0... = 5G-EA4: Not supported

.... .0.. = 5G-EA5: Not supported

.... ..0. = 5G-EA6: Not supported

.... ...0 = 5G-EA7: Not supported

1... .... = 5G-IA0: Supported

.1.. .... = 128-5G-IA1: Supported

..1. .... = 128-5G-IA2: Supported

...1 .... = 128-5G-IA3: Supported

.... 0... = 5G-IA4: Not supported

.... .0.. = 5G-IA5: Not supported

.... ..0. = 5G-IA6: Not supported

.... ...0 = 5G-IA7: Not supported

1... .... = EEA0: Supported

.1.. .... = 128-EEA1: Supported

..1. .... = 128-EEA2: Supported

...0 .... = 128-EEA3: Not supported

.... 0... = EEA4: Not supported

.... .0.. = EEA5: Not supported

.... ..0. = EEA6: Not supported

.... ...0 = EEA7: Not supported

1... .... = EIA0: Supported

.1.. .... = 128-EIA1: Supported

..1. .... = 128-EIA2: Supported

...0 .... = 128-EIA3: Not supported

.... 0... = EIA4: Not supported

.... .0.. = EIA5: Not supported

.... ..0. = EIA6: Not supported

.... ...0 = EIA7: Not supported

UE status

Element ID: 0x2b

Length: 1

0... .... = Spare: 0

.0.. .... = Spare: 0

..0. .... = Spare: 0

...0 .... = Spare: 0

.... 0... = Spare: 0

.... .0.. = Spare: 0

.... ..0. = N1 mode reg: UE is not in 5GMM-REGISTERED state

.... ...0 = S1 mode reg: UE is not in EMM-REGISTERED state

Item 2: id-UserLocationInformation

ProtocolIE-Field

id: id-UserLocationInformation (121)

criticality: reject (0)

value

UserLocationInformation: userLocationInformationNR (1)

userLocationInformationNR

nR-CGI

pLMNIdentity: 64f011

Mobile Country Code (MCC): China (460)

Mobile Network Code (MNC): Unknown (11)

0000 0000 0000 0000 0000 0000 0000 0000 0001 .... = nRCellIdentity: 0x000000001

tAI

pLMNIdentity: 64f011

Mobile Country Code (MCC): China (460)

Mobile Network Code (MNC): Unknown (11)

tAC: 136 (0x000088)

Item 3: id-RRCEstablishmentCause

ProtocolIE-Field

id: id-RRCEstablishmentCause (90)

criticality: ignore (1)

value

RRCEstablishmentCause: mo-Signalling (3)

Item 4: id-UEContextRequest

ProtocolIE-Field

id: id-UEContextRequest (112)

criticality: ignore (1)

value

UEContextRequest: requested (0)

Details

- Registration is first procedure that UE executes after being switched on.

When is it performed?

Initial registration

UE to connect to network after Power ON

Periodic Registration

Used by UEs in CM-IDLE mode

Mobility registration

When UE moves out of registration area

Emergency Registration

Used by UE when it wants to register only for emergency services.

Sequence Diagram

Allocate TMSI-AmfUeNgapId

Input : Message type: Registration request (0x41)

If Message type: Registration request (0x41) then allocate TMSI for NGAP -id

PCAP:

297 47.530339 HTTP2 10.233.102.158 43564 10.233.102.134 8082 Magic, SETTINGS[0], WINDOW_UPDATE[0], HEADERS[1]: POST /amf-ueidgen/v1/allocate/tmsi-amfuengapid, DATA[1]

Response :

amf_ue_ngap_id

newly_allocated_tmsi

Insert Stickiness

Discover AUSF

- requester-nf-type

- target-nf-type

- requester-plmn-list

- target-plmn-list

337 47.556192 HTTP2 10.233.102.158 47684 10.233.102.136 8082 Magic, SETTINGS[0], WINDOW_UPDATE[0], HEADERS[1]: GET /nnrf-disc/v1/nf-instances?requester-nf-type=AMF&service-names=nausf-auth&target-nf-type=AUSF&target-plmn-list=%5B%7B%22mcc%22:%22460%22,%22mnc%22:%2211%22%7D%5D&requester-plmn-list=%5B%7B%22mcc%22:%22460%22,%22mnc%22:%2211%22%7D%5D&routing-indicator=0, DATA[1]

AUSF Interaction

1. AMF -> AUSF

379 47.577265 HTTP2/JSON 10.233.102.158 39124 10.233.102.151 8082 Magic, SETTINGS[0], WINDOW_UPDATE[0], HEADERS[1]: POST /nausf-auth/v1/ue-authentications, DATA[1], JSON (application/json)

{

"servingNetworkName": "5G:mnc011.mcc460.3gppnetwork.org",

"supiOrSuci": "suci-0-460-11-0-0-0-0000000001"

}

2. AUSF -> NRF to search UDM

395 47.582120 HTTP2 10.233.102.151 50558 10.233.102.136 8082 Magic, SETTINGS[0], WINDOW_UPDATE[0], HEADERS[1]: GET /nnrf-disc/v1/nf-instances?requester-nf-type=AUSF&service-names=nudm-ueau&target-nf-type=UDM&target-plmn-list=%5B%7B%22mcc%22:%22460%22,%22mnc%22:%2211%22%7D%5D&routing-indicator=0, DATA[1]

3. Generate Auth Data

423 47.596608 HTTP2/JSON 10.233.102.151 41954 10.233.102.186 8082 Magic, SETTINGS[0], WINDOW_UPDATE[0], HEADERS[1]: POST /nudm-ueau/v1/suci-0-460-11-0-0-0-0000000001/security-information/generate-auth-data, DATA[1], JSON (application/json)

4. Response ( UDM -> AUSF )

439 47.607821 HTTP2/JSON 10.233.102.186 8082 10.233.102.151 41954 HEADERS[1]: 200 OK, DATA[1], JSON (application/json)

{

"authType": "5G_AKA",

"authenticationVector": {

"autn": "1eef1979cf8880000b1213b397c4fa6e",

"avType": "5G_HE_AKA",

"kausf": "8b18d5cc67cab8dacb6d9508e7c55a5ff9534851c2b672241fed0222d1b8a91f",

"rand": "48422b0173dac70601a7639e8fa3f021",

"xresStar": "407e46fc8df09518a2047ed2073f2745"

"supi": "imsi-460110000000001"

}

5. ( AUSF -> AMF )

447 47.620055 HTTP2/JSON 10.233.102.151 8082 10.233.102.158 39124 HEADERS[1]: 201 Created, DATA[1], JSON (application/3gpphal+json)

{

"5gAuthData": {

"autn": "1eef1979cf8880000b1213b397c4fa6e",

"hxresStar": "6cd18a485e84c7dbecb85fdeb1e40d4f",

"rand": "48422b0173dac70601a7639e8fa3f021"

"_links": {

"5g-aka": {

"href": "http://ausf-auth.radisys-ausf1:8082/nausf-auth/v1/ue_authentications/suci-0-460-11-0-0-0-0000000001"

}

"authType": "5G_AKA",

"servingNetworkName": "5G:mnc011.mcc460.3gppnetwork.org"

}

AMF -> UE ( Authentication Request )

451 47.626693 NGAP/NAS-5GS 10.233.102.150 172.27.29.125 SACK (Ack=1, Arwnd=212992) , DownlinkNASTransport, Authentication request

NGAP-PDU: initiatingMessage (0)

initiatingMessage

procedureCode: id-DownlinkNASTransport (4)

criticality: ignore (1)

value

DownlinkNASTransport

protocolIEs: 3 items

Item 0: id-AMF-UE-NGAP-ID

ProtocolIE-Field

id: id-AMF-UE-NGAP-ID (10)

criticality: reject (0)

value

AMF-UE-NGAP-ID: 2021

Item 1: id-RAN-UE-NGAP-ID

ProtocolIE-Field

id: id-RAN-UE-NGAP-ID (85)

criticality: reject (0)

value

RAN-UE-NGAP-ID: 2768240640

Item 2: id-NAS-PDU

ProtocolIE-Field

id: id-NAS-PDU (38)

criticality: reject (0)

value

NAS-PDU: 7e0056000200002148422b0173dac70601a7639e8fa3f02120101eef1979cf8880000b1213b397c4fa6e

Non-Access-Stratum 5GS (NAS)PDU

Plain NAS 5GS Message

Extended protocol discriminator: 5G mobility management messages (126)

0000 .... = Spare Half Octet: 0

.... 0000 = Security header type: Plain NAS message, not security protected (0)

Message type: Authentication request (0x56)

0000 .... = Spare Half Octet: 0

NAS key set identifier - ngKSI

.... 0... = Type of security context flag (TSC): Native security context (for KSIAMF)

.... .000 = NAS key set identifier: 0

ABBA

Length: 2

ABBA Contents: 0000

Authentication Parameter RAND - 5G authentication challenge

Element ID: 0x21

RAND value: 48422b0173dac70601a7639e8fa3f021

Authentication Parameter AUTN (UMTS and EPS authentication challenge) - 5G authentication challenge

Element ID: 0x20

Length: 16

AUTN value: 1eef1979cf8880000b1213b397c4fa6e

SQN xor AK: 1eef1979cf88

AMF: 8000

MAC: 0b1213b397c4fa6e

UE -> AMF (Authentication Response)

NGAP-PDU: initiatingMessage (0)

initiatingMessage

procedureCode: id-UplinkNASTransport (46)

criticality: ignore (1)

value

UplinkNASTransport

protocolIEs: 4 items

Item 0: id-AMF-UE-NGAP-ID

ProtocolIE-Field

id: id-AMF-UE-NGAP-ID (10)

criticality: reject (0)

value

AMF-UE-NGAP-ID: 2021

Item 1: id-RAN-UE-NGAP-ID

ProtocolIE-Field

id: id-RAN-UE-NGAP-ID (85)

criticality: reject (0)

value

RAN-UE-NGAP-ID: 2768240640

Item 2: id-NAS-PDU

ProtocolIE-Field

id: id-NAS-PDU (38)

criticality: reject (0)

value

NAS-PDU: 7e00572d10407e46fc8df09518a2047ed2073f2745

Non-Access-Stratum 5GS (NAS)PDU

Plain NAS 5GS Message

Extended protocol discriminator: 5G mobility management messages (126)

0000 .... = Spare Half Octet: 0

.... 0000 = Security header type: Plain NAS message, not security protected (0)

Message type: Authentication response (0x57)

Authentication response parameter

Element ID: 0x2d

Length: 16

RES: 407e46fc8df09518a2047ed2073f2745 << Should match with "xresStar": "407e46fc8df09518a2047ed2073f2745"

Item 3: id-UserLocationInformation

ProtocolIE-Field

id: id-UserLocationInformation (121)

criticality: ignore (1)

value

UserLocationInformation: userLocationInformationNR (1)

userLocationInformationNR

nR-CGI

pLMNIdentity: 64f011

Mobile Country Code (MCC): China (460)

Mobile Network Code (MNC): Unknown (11)

0000 0000 0000 0000 0000 0000 0000 0000 0001 .... = nRCellIdentity: 0x000000001

tAI

pLMNIdentity: 64f011

Mobile Country Code (MCC): China (460)

Mobile Network Code (MNC): Unknown (11)

tAC: 136 (0x000088)

RedCap

November 19, 2024 No comments

3Gpp

Find document based on document number : 3GPP document search by file name | Netovate

RedCap

Blog : The 3G4G Blog: RedCap

PPT Slide + Links : Beginners: Introduction to 5G Reduced Capability (RedCap) Devices

3GPP CRs : How to find RedCap in 3GPP

In Spec

23.501 Section 5.41 NR RedCap UEs differentiation

Section 5.3.2.3

The AMF may also determine more precise RAT Type information based on further information received from NGRAN:

- The AMF may determine the RAT Type to be LTE-M as defined in clause 5.31.20; or

- The AMF may determine the RAT Type to be NR using unlicensed bands, as defined in clause 5.4.8.

- The AMF may determine the RAT Type to be one of the RAT types for satellite access, as defined in

clause 5.4.10.

- The AMF may determine the RAT Type to be NR RedCap as defined in clause 5.41.

Section 5.41

5.41 NR RedCap UEs differentiation

This functionality is used by the network to identify traffic to/from UEs accessing over NR RedCap, e.g. for charging

differentiation.

An NR RedCap UE using NR shall provide an NR RedCap indication to the NG-RAN during RRC Connection

Establishment procedure as defined in TS 38.300 [27].

When the UE has provided an NR RedCap indication to the NG-RAN during RRC Connection Establishment, the NGRAN

shall provide an NR RedCap Indication to the AMF in the Initial UE Message (see clause 4.2.2.2.1 of

TS 23.502 [3] and TS 38.413 [34]).

When the AMF receives an NR RedCap Indication from NG-RAN in an Initial UE Message, the AMF shall store the

NR RedCap Indication in the UE context, consider that the RAT type is NR RedCap and signal it accordingly to the

SMSF during registration procedure for SMS over NAS, to the SMF during PDU Session Establishment or PDU

Session Modification procedure. The PCF will also receive the NR RedCap RAT type indication when applicable, from

the SMF during SM Policy Association Establishment or SM Policy Association Modification procedure.

During handover from E-UTRA to NR, the target NG-RAN (i.e. gNB) provides the NR RedCap indication to AMF in

NGAP Path Switch Request message during Xn handover, or NGAP Handover Request Acknowledge message during

N2 handover (including intra 5GS N2 handover and EPS to 5GS handover) based on the UE capability information

provided by the source RAN to the target RAN as specified in TS 38.300 [27].

The NFs interacting with CHF shall include the NR RedCap as RAT type.

Upon AMF change, the source AMF shall provide the "NR RedCap Indication" to the target AMF.

Kubernetes - Namespace

September 17, 2024Kubernetes No comments

Kubernetes - Namespace

Default namespace created by Kubernetes

kube-system
kube-public
default

How it is helpful ?

These different namespace

can be used by same cluster for DEV and PROD environment.
they will have isolated resources between them so that DEV will have their own resource and PROD will have their own resource.
they will have their own policies that define who can do what

Each namespace has a max limit of resources and are not allowed to use more than its allowed limit.
We can define policy such that for example, while working in DEV environment, we can't modify a resource of PRODUCTION.

Example usage of custom namespace.

Dev
Test
Prod

How to name resources of a namespace?

Same namespace

Resources in same namespace ca access via db-service

Different namespace

Resources in other namespace can access resources in other namespace via ( say DEV resources via - db-service.dev.svc.cluster.local

Name details

db-service.dev.svc.cluster.local

db-service - Name of the service
dev - namespace
svc - service
cluster.local - domain.

How to create Namspace Or Pod Inside Namespace

Create in default namespace

kubectl create -f pod-definition.yml -f

Create a particular namespace

kubectl create -f pod-definition --namespace dev
kubectl create -f pod-definition -n dev

Create a Namespace

kubectl create -f namespace-dev.yaml
kubectl create namespace dev
Sample Yaml file for Namespace

apiVersion: v1
kind: Namespace
metadata:

name: dev

Create POD under a namespace through Yaml file

apiVersion: v1
kind: Pod
metadata

name: myapp-pod
namespace: dev
label

app: myapp
type: front-end

spec

container:

name: nginx-container
image: nbinx

Accessing Namespace

Scenario -1 : Access default namespace

kubectl get pods
kubectl get pods --namespace dev
kubectl get pods --namespace prod

Change the default namespace to namespace = dev

kubectl config set-context $(kubectl config current-context) --namespace dev
kubectl get pods <<<< This will show Pods from namespace = DEV.
kubectl get pods --namespace default << To access default namespace
kubectl get pods --namespace prod << To access PROD namespace

Resource Quota

Resources can be limited in a namespace.

apiVersion: v1
kind: ResourceQuota
metadata:

name: compute-quota
namespace: dev

spec:

hard:

pods: "10",
requests-cpu: "4"
requests-memory: 5Gi
limts-cpu: "10"
limits-memory: 10Gi

Kubernetes- Deployment

September 12, 2024Kubernetes No comments

Kubernetes- Deployment

- Defines how to deploy application in production environment.

Scenarios

Old instance running - Multiple Pod having applications are running in production environment.
New version of application is available - need to upgrade seamlessly- without any downtime.

Rolling update

For this we don't want to upgrade all of them at once as this may impact accessibility.
One by one upgrade - And we might want to upgrade one after other.

In case of failure - we should be able to rollback the upgrade.
Multiple change to environment -

Ex - Scaling the environment, Modifying resource allocation etc.
And this change should be done for all PODS together and then activated for all Pods as the same time.

Kubernetes Deployment

Comes at the top of the hierarchy.

Comes at top of Pod and Replica Set.

Available with

Rolling update
Undo changes
Pause changes
Resume changes

How to create deployment

Yaml file

same as ReplicaSet except for change in KIND.

apiVersion: apps/v1

kind: Deployment << Only change done for Deployment

metadata:

labels:

app: myapp

type: front-end

spec:

template: <<< Here need to provide template for POD. We just to insert metadata + spec section of POD.

metadata:

labels:

app: myapp

type: front-end

spec:

containers:

image: nginx

replicas: 3 <<< This is sibling of template

selector:

matchLabels:

type: front-end

Commands

Kubernetes Architecture, POD, ReplicaSet & Replica Controller

August 27, 2024Kubernetes No comments

Kubernetes Architecture, POD, ReplicaSet & Replica Controller

1. Introduction

What is Node ?

Node is a machine - Physical or Virtual on which Kubernetes is installed,
Node is where containers will be launched by Kubernetes.

What will happen to Nodes in which application is running fails.

Application goes down -- Means Kubernetes goes down.

Why do we need to have more than one node OR Why do we need CLUSTER?

Because of one node on which Kuberneres is installed goes down then application will also go down. So for redundancy, we need to have more than one node.
So we have more than one node grouped together.

So even if one node goes down, application is still accessible from other nodes.

Now we have CLUSTER ?

- So who is managing cluster ?

- Where is the information about members of clusters stored ?

- How are nodes monitored ?

- When a node failed, how do u move workload of one node to other worked node ?

This is the work of Master node. ( M, S, M, F )

Manage, Store, Monitor, Failure Handling

When u install Kubernetes, what components are installed?

Api server

Acts as Front end for kubernetes
User, Management Devices, Command Line interfaces

talk to API server to interact with Kubernetes cluster.

etcd

distributed, reliable key-value storage to store

all data used to manage cluster.
Also implements locks in the cluster, so that there is no conflict

kubelet

agent that runs on each node of the cluster.
makes sure that conatiners are running on nodes as expected.

container runtime

Underlying software that run containers.

For example - docker.

controller

Brain behind orchestration.
Responds when nodes, containers or end points goes down.
Take decision to bringup new containers in case of failure.

schedular

For distributing work across containers on various nodes.

Master & Worker Nodes

How some node became master and some node became worker nodes ?

- Master node that has

Kube-API server, becomes master node.

All information is stored in KEY-VALUE ( etcd ) store in master.

Master also has

controller and
schedular

- Worked node has

kubelet agent, so it becomes worker node.

Through kubelet-agent worker node can interact with MASTER.

TO provide health information of worker node.
And CARRY out instruction from MASTER.

What is kubectl

- This is KUBE command line control

kubectl run

to install cluster

kubectl cluster-info

View information about cluster

kubectl get nodes

To list all nodes of the cluster

Docker Vs Container

Docker

- container solution.

Kubernetes

kubernetes came to orchestrate docker. and they were tightly coupled.
But later Kubernetes provided a layer Container Runtime Interface ( CRI ) that can take into any container solution ex - docker, rkt, as long as they adhere to OCI standard (Open Container standard)
CRTICTL

This is command line interface (CLI command) for CRI
This will work for any container intarface.

POD

Steps -

- Application is built

- Has been put in docker image

- And Kubernetes can pull the image.

Aim

- Deploy APplication

- In the form of containers

- On a set of machines

- That are configured as worker nodes.

- In a cluster

But

- Kubernetes does not deploy container directly, it has to be put in POD.

Scale up/down

- We can't add new container inside POD

We need to create new POD in same node.
We can create new POD and new Node.

Concept of multi-container pod

POD can have multiple container.
But generally they dont have multiple container of same kind

We can have hlper container

Ex - Processing file,

YAML with Kubernetes

Creating POD using YAML based configuration file

Command to create a POD

kubectl create -f pod.yml

Mandatory Values in K8 yaml file

- apiVersion

- Not a KEY/VALUE, we just pass a string

- API version that we are using to create Kubernetes

- Example value - v1 , app/v1

- kind

- Not a KEY/VALUE, we just pass a string

- type of objext we are trying to create

- Example - POD, Service, ReplicaSet, Deployment

- Metadata

- This is dictionary.

- This is data of the object.

-- Example - Name, Label etc

-- Here 'name' and labels are dictionary. (have KEY/Value)

- NAME and IMAGE are sibling

- Under "MetaData" we can have only "name" and "label"

- But under "label" we can define any "key". "value" pair.

- Spec

- 'Spec' is a dictionary, So Add property under it.

- Below 'spec', there is 'container'. 'container' is also a list/array

- because there can be multiple containers in a pod.

- So first element in a list indicate that it is first item in the list ( - name )

- Here name & spec is element inside 'container'

Replica Sets / Replica Controllers.

Replica Controllers

- Are the brain behind Kubernetes

- Have processes that

- Monitor Kubernetes objects

- And manage accordingly.

Question - What is a replica and why do we need replication-controller ?

Suppose we have a node + POD + Container running our application
What will happen if our application crashes ?
So users will no longer to access our application.

Solution

- If we don't want any disruption, we will need to have multiple POD so that there will not disruption. Even if one fails, other POD will still be accessible.

Replication Controller

helps running multiple instance of same POD in a Kubernetes cluster.

Two reasons for Replication Controller

High Availability

And so it provides high availability.
So if one pod goes down, replication controller quickly instantiates another pod.

Load Balancing

If demand increases, replication controller creates Pods

On same Node
Or No multiple Nodes.

Two terms - Replication Controller vs Replica Set

There is minor difference between both but more or less they are same.

Replication Controller - older way
Replica Set - newer way.

How to create Replication Controller - using Yaml file.

apiVersion: v1

kind: Replication Controller

metadata:

name: myapp-rc

labels:

app: myapp

type: fromt-end

spec: spec defines what in inside the KIND. As POD is inside Replication Controller. So provide template of the Pod.

template: <<< Here need to provide template for POD. We just to insert metadata + spec section of POD.

metadata:

labels:

app: myapp

type: front-end

spec:

containers:

image: nginx

But we have something still missing.

We have not specified how many PODs to be created?
Or how many replicas of POD to be available all the time?
Solution : Add 'replicas: 3

apiVersion: v1

kind: Replication Controller

metadata:

name: myapp-rc

labels:

app: myapp

type: fromt-end

spec: spec defines what in inside the KIND. As POD is inside Replication Controller. So provide template of the Pod.

template: <<< Here need to provide template for POD. We just to insert metadata + spec section of POD.

metadata:

labels:

app: myapp

type: front-end

spec:

containers:

image: nginx

replicas: 3 <<< This is sibling of template

How to create ReplicaSet - using Yaml file.

apiVersion: apps/v1 << Note for ReplicationController this is - v1

kind: ReplicaSet

metadata:

labels:

app: myapp

type: front-end

spec:

template: <<< Here need to provide template for POD. We just to insert metadata + spec section of POD.

metadata:

labels:

app: myapp

type: front-end

spec:

containers:

image: nginx

replicas: 3 <<< This is sibling of template

selector: << Only got replicaSet

matchLabels:

type: front-end

selector

Defines which POD fall in it.We can define multiple labels.

Can have labels of PODS define in the same definition
Can have labels defined somewhere else.

Labels & Selectors

Monitor POD of specified LABEL specified as part of matchLabels
Always keep the 3 replicas of the POD instance.
ReplicaSet is 'process' that monitors the PODS and if any POD fails, it creates new POD.

How ReplicaSet knows which POD to monitor ?

This is done by labels provided as part of matchLabels.

How to change replicas ?

Two commands

replace
scale

Blogger templates

Tuesday, 7 January 2025

44. Env variables

Other ways to define ENV variables

ConfigMaps

How to create config-maps ( 2 ways )

Imperative way to create config-map

Declarative way for config-map

View Configmap

Config map in yaml file

Different ways of config-map

37. Define, Build and Modify Container Images.

Why ?

What are the steps if we have to deploy our application manually ?

Docker file with file name = <file-name>

Build docker

PUSH Docker

38. Command and Arguments in Docker ( CMD, ENTRYPOINT )

40. Command and Argument in K8

Sunday, 15 December 2024

Registration request

NGAP Message

Details

When is it performed?

Sequence Diagram

Allocate TMSI-AmfUeNgapId

Insert Stickiness

Discover AUSF

AUSF Interaction

AMF -> UE ( Authentication Request )

UE -> AMF (Authentication Response)

Tuesday, 19 November 2024

3Gpp

RedCap

In Spec

23.501

Section 5.41 NR RedCap UEs differentiation

Section 5.3.2.3

5.41 NR RedCap UEs differentiation

Tuesday, 17 September 2024

Kubernetes - Namespace

Default namespace created by Kubernetes

How it is helpful ?

Example usage of custom namespace.

How to name resources of a namespace?

Name details

Thursday, 12 September 2024

Kubernetes- Deployment

Kubernetes Deployment

How to create deployment

Yaml file

Commands

Tuesday, 27 August 2024

Kubernetes Architecture, POD, ReplicaSet & Replica Controller

1. Introduction

Master & Worker Nodes

What is kubectl

Docker Vs Container

Docker

Kubernetes

POD

YAML with Kubernetes

Creating POD using YAML based configuration file

Command to create a POD

Mandatory Values in K8 yaml file

Replica Sets / Replica Controllers.

Replica Controllers

Question - What is a replica and why do we need replication-controller ?

Solution

Two terms - Replication Controller vs Replica Set

How to create Replication Controller - using Yaml file.

But we have something still missing.

How to create ReplicaSet - using Yaml file.

selector

Defines which POD fall in it.We can define multiple labels.

Labels & Selectors

How ReplicaSet knows which POD to monitor ?

How to change replicas ?

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