Technology

Serve rpm repository from AWS S3

joaocosta, , , , Leave a comment

Some notes on how packages.zonalivre.org was setup to be serve custom rpm packages from an AWS S3 bucket, mostly based on http://blog.celingest.com/en/2014/09/17/create-your-own-yum-rpm-repository-using-amazon-s3/ .

Make sure the aws cli is setup on the workstation:

mkdir -p ~/.aws
cat <<EOF >~/.aws/config
[default]
region = us-east-1
EOF

cat <<EOF >~/.aws/credentials
[default]
aws_access_key_id = AWS_ACCESS_KEY
aws_secret_access_key = AWS_SECRET_ACCESS_KEY
EOF

From the workstation, create a new S3 bucket. If you intend to use your own domain name, it’s important that the bucket has the same name as the domain you intend to use.

Also create a user (to upload files to the bucket) and give this user access to your S3 buckets.

aws s3 mb s3://packages.zonalivre.org
aws iam create-user --user-name zonalivre-rpm-repo
aws iam create-access-key --user-name zonalivre-rpm-repo
cat <<EOF >zonalivre-rpm-repo_policy.json
{
    "Version": "2012-10-17",
    "Statement": [
    {
        "Effect": "Allow",
        "Action": "s3:*",
        "Resource": ["arn:aws:s3:::packages.zonalivre.org/*", "arn:aws:s3:::packages.zonalivre.org"]
    },
    {
        "Effect": "Allow",
        "Action": "s3:ListAllMyBuckets",
        "Resource": "*",
        "Condition": {}
    }
    ]
}
EOF
aws iam put-user-policy --user-name zonalivre-rpm-repo --policy-name zonalivre-rpm-repo-bucket-access --policy-document file://zonalivre-rpm-repo_policy.json

From the workstation, check user is configured correctly

aws iam list-user-policies --user-name zonalivre-rpm-repo
{
    "PolicyNames": [
        "zonalivre-rpm-repo-bucket-access"
    ]
}

On the S3 console, click “Properties”->”Static Website Hosting”->”Enable static website hosting”. You’ll also need to provide an Index document. Just enter index.html.

Create a DNS alias to point to the new bucket. After this is setup and propagated, it should look like:

host packages.zonalivre.org
packages.zonalivre.org is an alias for packages.zonalivre.org.s3.amazonaws.com.
packages.zonalivre.org.s3.amazonaws.com is an alias for s3-directional-w.amazonaws.com.
s3-directional-w.amazonaws.com is an alias for s3-1-w.amazonaws.com.
s3-1-w.amazonaws.com has address 54.231.1.137

Install required packages on build server. In this particular case, packages are installed as per chef recipe https://github.com/joaocosta/chef-repo/blob/master/cookbooks/fx-build/recipes/default.rb .

The important one here is s3cmd, available as part of the epel repo.

On the build server, configure s3cmd

s3cmd --configure
...
s3cmd ls
2016-01-24 09:03  s3://packages.zonalivre.org

Still on the build server, generate a public/private GPG key pair.
See https://technosorcery.net/blog/2010/10/10/pitfalls-with-rpm-and-gpg/ for a number of gotchas around using gpg keys to sign rpms. Some of the bugs described in the article may have been fixed by now.

gpg --gen-key
# Choose signing only RSA key
# Your key cannot have any subkeys
# Your key must be > 1024-bit (i used 2048)

gpg needs randomness to generate keys. The more entropy there is in your system, the quicker the keys will be generated. You can check how much entropy is available with:

watch -n 1 cat /proc/sys/kernel/random/entropy_avail

There are multiple ways of generating additionally entropy so that key generation happens quicker, such as moving your mouse around, hitting the keyboard, or using specialized software. A quick and dirty way of generating entropy is to run this in a separate shell:

find / -type f | egrep -v "(/dev|/proc|/sys/kernel)" | xargs md5sum

Once key generation completes, list generated keys:

gpg --list-keys
/root/.gnupg/pubring.gpg
------------------------
pub   2048R/859031CB 2016-01-24
uid                  Builder <packages@zonalivre.org>

And export the public key:

gpg --output ~/RPM-GPG-KEY-zonalivre-rpm-repo --armor --export 859031CB

Add gpg rpm macros and remember to replace YOUR_GPG_KEY_ID .
In my case, this is 859031CB.

cat <<EOF >~/.rpmmacros
%signature gpg
%_gpg_path $HOME/.gnupg
%_gpg_name <YOUR_GPG_KEY_ID>
%_gpg_bin /usr/bin/gpg
%packager Builder <packages@zonalivre.org>
%_topdir $HOME/rpmbuild
EOF

Now import GPG public key into rpm

rpm --import ~/RPM-GPG-KEY-zonalivre-rpm-repo

Confirm key has been imported into rpm

rpm -q gpg-pubkey --qf '%{name}-%{version}-%{release} --> %{summary}\n' | grep zona
gpg-pubkey-859031cb-56a4c669 --> gpg(Builder <packages@zonalivre.org>)

Create the .repo file

cat <<EOF >~/zonalivre-rpm.repo
[zonalivre-rpm-repo]
name=name=Extra Packages from Zonalivre RPM Repository -
baseurl=https://packages.zonalivre.org/zonalivre/$releasever/$basearch/
enabled=1
gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-zonalivre-rpm-repo
gpgcheck=1
EOF

Create rpmbuild tree

rpmdev-setuptree

To package this repo as an rpm, create a spec file

cat <<EOF >~/rpmbuild/SPECS/zonalivre-rpm.spec
# Zonalivre RPM Repository configuration files and GPG key
%define name zonalivre-rpm-repo
%define version 1
%define release 0.1
%define buildroot %{_topdir}/%{name}-%{version}-root
BuildArch:  noarch
BuildRoot:  %{buildroot}
Summary:    Zonalivre RPM Repository
License:    MIT
Name:       %{name}
Version:    %{version}
Release:    %{release}
Group:      Development/Tools

%description
Package containing Zonalivre RPM Repository configuration files and GPG key.

%prep
exit 0

%build

%install
rm -rf $RPM_BUILD_ROOT
mkdir -p $RPM_BUILD_ROOT%{_sysconfdir}/yum.repos.d/
mkdir -p $RPM_BUILD_ROOT%{_sysconfdir}/pki/rpm-gpg/
cp -p ~/zonalivre-rpm.repo $RPM_BUILD_ROOT%{_sysconfdir}/yum.repos.d/
cp -p ~/RPM-GPG-KEY-zonalivre-rpm-repo $RPM_BUILD_ROOT%{_sysconfdir}/pki/rpm-gpg/

%clean
rm -rf $RPM_BUILD_ROOT

%files
%defattr(-,root,root,-)
/etc/yum.repos.d/zonalivre-rpm.repo
/etc/pki/rpm-gpg/RPM-GPG-KEY-zonalivre-rpm-repo

%changelog
* Sun Jan 24 2016 Builder <builder@zonalivre.org> 1.0.1
- First release.
EOF

Create RPM

cd ~/rpmbuild/SPECS/
rpmbuild -v -ba --sign --clean zonalivre.spec

Verify package signature

rpm --checksig ~/rpmbuild/RPMS/noarch/zonalivre-rpm-repo-1-0.1.noarch.rpm 
/root/rpmbuild/RPMS/noarch/zonalivre-rpm-repo-1-0.1.noarch.rpm: rsa sha1 (md5) pgp md5 OK

Create and populate the final repository structure

mkdir -vp ~/packages.zonalivre.org/zonalivre/7/{x86_64,noarch}
cp ~/RPM-GPG-KEY-zonalivre-rpm-repo ~/packages.zonalivre.org/zonalivre/
cp -rv ~/rpmbuild/RPMS/* ~/packages.zonalivre.org/zonalivre/7/
for repo in ~/packages.zonalivre.org/zonalivre/7/{x86_64,noarch}; do
  createrepo -v --deltas ${repo}/
done

Sync the repository structure to AWS S3:

s3cmd -P sync ~/packages.zonalivre.org/ s3://packages.zonalivre.org/

And finally, our repo can be installed in a client:

yum localinstall http://packages.zonalivre.org/zonalivre/7/noarch/zonalivre-rpm-repo-1-0.1.noarch.rpm

References:

Serve rpm repository from AWS S3

docker_script

joaocostaLeave a comment

Install

curl -sSL -O https://get.docker.com/builds/Linux/x86_64/docker-1.9.1 && chmod +x docker-1.9.1 && sudo mv docker-1.9.1 /usr/local/bin/docker

Run daemon

sudo /usr/local/bin/docker daemon

Run client

docker info

Docker Images vs Docker Containers

Images

docker images
docker search linux
docker pull ubuntu
docker images

This does not cover how to create your own images

Containers

docker run ubuntu echo Hello World
docker ps
docker ps -a
docker logs $IMAGE_NAME

Running a container with a custom name

docker run --help | less
docker run --name HelloWorld ubuntu echo Hello World
docker ps -a
docker inspect HelloWorld | less
docker rm HelloWorld

Running an interactive container

docker run --name ubuntu_shell -t -i  ubuntu bash
exit
docker start ubuntu_shell
docker exec ubuntu_shell ifconfig
docker exec -t -i ubuntu_shell bash
exit
docker ps
docker attach ubuntu_shell
exit
docker ps
docker rm ubuntu_shell

Running a web application with docker

docker run --name web -d -P training/webapp python app.py
# See https://github.com/docker-training/webapp
docker ps # Note randomly assigned port mapping
docker port web 5000
docker rm -f web
docker run --name web -d -p 5000:5000 training/webapp python app.py
docker port web 5000
curl --noproxy localhost http://localhost:5000/
docker logs web
docker top web
docker rm -f web

Network containers

Check existing docker networks

docker network ls
docker network inspect bridge

Create new network

docker network create -d bridge privatenet
docker network inspect privatenet

Start DB container in privatenet

docker run -d --net=privatenet --name db training/postgres  # See https://github.com/docker-training/postgres

Start Web container in bridged network

docker run --name web -d -p 5000:5000 training/webapp python app.py
docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' web

Check IP Addresses of each container

docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' db
docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' web

Check DB container can’t access web container

docker exec -it db bash
ping $WEB_IP_ADDRESS
exit

docker network connect privatenet web
docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' web
docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' db
docker exec -it db bash
ping $WEB_PRIVATE_NET_IP_ADDRESS
ping web
exit
docker rm -f web db

Mounting volumes in containers

Volume characteristics

  • Initialized when a container is created
  • Can be shared and reused among containers
  • Changes to a data volume are not included when an image is updated
  • Data volumes persist even if the container is deleted

Sharing data between container and host

mkdir myfiles
echo Hello > myfiles/hello
docker run -it --name ubuntu -v $PWD/myfiles:/myfiles ubuntu bash
ls -l /myfiles
exit
docker inspect ubuntu | less # search for Mounts

Sharing data between containers

TODO

docker_script

Time individual statements in bash

joaocosta, , Leave a comment

Sometimes the 1000+ line bash script you inherited at work takes 3 hours to complete and you’re not sure where the time is being spent. StackOverflow has some good answers on this topic:

http://stackoverflow.com/questions/5014823/how-to-profile-a-bash-shell-script
http://stackoverflow.com/questions/18039751/how-to-debug-a-bash-script-and-get-execution-time-per-command

The simplest one that gives me the most value for the least effort (imo) is:

PS4='+[${SECONDS}s][${BASH_SOURCE}:${LINENO}]: ${FUNCNAME[0]:+${FUNCNAME[0]}(): }'

#!/bin/bash

PS4='+[${SECONDS}s][${BASH_SOURCE}:${LINENO}]: ${FUNCNAME[0]:+${FUNCNAME[0]}(): }'
set -x

echo 1
sleep 1
echo 2
sleep 2
echo 3

This produces the following output:

joao@home:~> ./timings.sh
+[0s][./timings.sh:7]: echo 1
1
+[0s][./timings.sh:8]: sleep 1
+[1s][./timings.sh:9]: echo 2
2
+[1s][./timings.sh:10]: sleep 2
+[3s][./timings.sh:11]: echo 3
3

Happy bash profiling !

Time individual statements in bash