I'm trying to generate an SSL certificate with certbot/certbot docker container in kubernetes. I am using Job controller for this purpose which looks as the most suitable option. When I run the standalone option, I get the following error:

Failed authorization procedure. staging.ishankhare.com (http-01): urn:ietf:params:acme:error:connection :: The server could not connect to the client to verify the domain :: Fetching http://staging.ishankhare.com/.well-known/acme-challenge/tpumqbcDWudT7EBsgC7IvtSzZvMAuooQ3PmSPh9yng8: Timeout during connect (likely firewall problem)

I've made sure that this isn't due to misconfigured DNS entries by running a simple nginx container, and it resolves properly. Following is my Jobs file:

apiVersion: batch/v1
kind: Job
metadata:
  #labels:
  #  app: certbot-generator
  name: certbot
spec:
  template:
    metadata:
      labels:
        app: certbot-generate
    spec:
      volumes:
        - name: certs
      containers:
        - name: certbot
          image: certbot/certbot
          command: ["certbot"]
          #command: ["yes"]
          args: ["certonly", "--noninteractive", "--agree-tos", "--staging", "--standalone", "-d", "staging.ishankhare.com", "-m", "me@ishankhare.com"]

          volumeMounts:
            - name: certs
              mountPath: "/etc/letsencrypt/"
              #- name: certs
              #mountPath: "/opt/"
          ports:
            - containerPort: 80
            - containerPort: 443
      restartPolicy: "OnFailure"

and my service:

apiVersion: v1
kind: Service
metadata:
  name: certbot-lb
  labels:
    app: certbot-lb
spec:
  type: LoadBalancer
  loadBalancerIP: 35.189.170.149
  ports:
    - port: 80
      name: "http"
      protocol: TCP
    - port: 443
      name: "tls"
      protocol: TCP
  selector:
    app: certbot-generator

the full error message is something like this:

Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator standalone, Installer None
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for staging.ishankhare.com
Waiting for verification...
Cleaning up challenges
Failed authorization procedure. staging.ishankhare.com (http-01): urn:ietf:params:acme:error:connection :: The server could not connect to the client to verify the domain :: Fetching http://staging.ishankhare.com/.well-known/acme-challenge/tpumqbcDWudT7EBsgC7IvtSzZvMAuooQ3PmSPh9yng8: Timeout during connect (likely firewall problem)
IMPORTANT NOTES:
 - The following errors were reported by the server:

   Domain: staging.ishankhare.com
   Type:   connection
   Detail: Fetching
   http://staging.ishankhare.com/.well-known/acme-challenge/tpumqbcDWudT7EBsgC7IvtSzZvMAuooQ3PmSPh9yng8:
   Timeout during connect (likely firewall problem)

   To fix these errors, please make sure that your domain name was
   entered correctly and the DNS A/AAAA record(s) for that domain
   contain(s) the right IP address. Additionally, please check that
   your computer has a publicly routable IP address and that no
   firewalls are preventing the server from communicating with the
   client. If you're using the webroot plugin, you should also verify
   that you are serving files from the webroot path you provided.
 - Your account credentials have been saved in your Certbot
   configuration directory at /etc/letsencrypt. You should make a
   secure backup of this folder now. This configuration directory will
   also contain certificates and private keys obtained by Certbot so
   making regular backups of this folder is ideal.

I've also tried running this as a simple Pod but to no help. Although I still feel running it as a Job to completion is the way to go.