Ruby on Rails: Operation now in progress - connect(2) would block - ruby-on-rails

Question

I'm working on a site someone else made. There is a production version.
I'm trying to send emails to users whose properties haven't been updated in 30 days.
Everything works until I try to use deliver_later. The reason I'm using deliver_later is because deliver_now results in an issue of sending too many emails per second. I'm currently using Mailtrap for testing, but I assume I will run into that sort of issue on production.
So I opted to wait 1 second for each email:
#testproperties = Property.has_not_updated.includes(:user)
#testproperties.each do |property|
UserMailer.with(property: property, user: property.user).check_listing.deliver_later(wait:1.seconds)
end
This results in IO::EINPROGRESSWaitWritable Operation now in progress - connect(2) would block
And nothing sends.
I'm not sure how to solve this issue.
Edit:
I can see on the production site that I can visit the route /sidekiq. The routes file has this block:
authenticate :user, lambda { |u| u.admin? } do
mount Sidekiq::Web => '/sidekiq'
end
I can view the web interface and see all the jobs. It's all working there. But I need to access development version running on localhost:3000.
Trying to access this locally still results in:
Operation now in progress - connect(2) would block
# # Socket#connect
def connect_nonblock(addr, exception: true)
__connect_nonblock(addr, exception)
end
end
Sidekiq.rb:
require 'sidekiq'
unless Rails.env.test?
host = 'localhost'
port = '6379'
namespace = 'sitename'
Sidekiq.configure_server do |config|
config.redis = { url: "redis://#{host}:#{port}", namespace: namespace }
schedule_file = "config/schedule.yml"
if File.exists?(schedule_file)
Sidekiq::Cron::Job.load_from_hash YAML.load_file(schedule_file)
end
config.server_middleware do |chain|
chain.add Sidekiq::Status::ServerMiddleware, expiration: 30.minutes
end
config.client_middleware do |chain|
chain.add Sidekiq::Status::ClientMiddleware, expiration: 30.minutes
end
end
Sidekiq.configure_client do |config|
config.redis = { url: "redis://#{host}:#{port}", namespace: namespace }
config.client_middleware do |chain|
chain.add Sidekiq::Status::ClientMiddleware, expiration: 30.minutes
end
end
end
for cable.yml:
development:
adapter: async
url: redis://localhost:6379/1
channel_prefix: sitename_dev
test:
adapter: async
production:
adapter: redis
url: redis://localhost:6379/1
channel_prefix: sitename_production

Answer 1

The production server is running Ubuntu and they already installed redis-server.
I had not installed that locally. (I'm using Ubuntu through Windows WSL)
sudo apt install redis-server
I can now access the web interface.

Answer 2

Make sure that Redis is started:
sudo service redis-server restart