Creating a Hadoop cluster with cobbler and ansible. Easy and fully automated.

1. GoDataDriven
PROUDLY PART OF THE XEBIA GROUP
@krisgeus
krisgeusebroek@godatadriven.com
Bare metal Hadoop
provisioning
Kris Geusebroek
Big Data Hacker
With ansible and cobbler
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2. -- Big Data Borat
“Give man Hadoop cluster he gain
insight for a day. Teach man build
Hadoop cluster he soon leave for
better job. #bigdata”
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3. -- Kris Geusebroek
“We’re hiring”
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4. Don’t want to...
Manually install everything needed for a Hadoop
cluster...
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5. Separate layers...
- Hardware
- OS
- Basic install and configuration (Firewalls, IPSec, IPV6,
NTPd, raise ulimits, disk formatting and mounting)
- Cluster install (Cloudera Manager or Hortonworks
Data Platform)
- Extra stuff (Monitoring Ganglia, R & R-packages, ......)
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6. Want...
- Horizontal scaling: Effort for an extra machine is
minimal
- Commodity Industry standard hardware
- So cope with errors, malfunctioning, re-installation
- Multiple clusters
- Experiment first with appropriate configuration for a
specific goal
-Think memory, hard disks, number of nodes
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7. Want...
- Automate all the tasks for every layer
- Parameterise a lot
- Simple configuration of the separate layers
- Definition of roles (masternode, datanode etc.)
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8. Possible with...
Vendor specific tools
problem here is they can do only a subset of all tasks
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9. What we have done here...
Nothing new, just another possibility
Nothing tool specific
- demo installs Cloudera Manager, but works also with
Hortonworks Data Platform.
Most important is:
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10. Stack...
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11. -- Big Data Borat
“Essentially, this solution is CoSSaaS.”
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12. -- Big Data Borat
“Essentially, this solution is CoSSaaS.
(Couple of Shell Scripts as a Service)”
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13. Cobbler...
Cobbler used for
- CMS
- DHCP server
- OS image hosting
- OS kickstart
cobblerd.org
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14. Ansible...
Ansible used for
-Tying it all together
- Initial setup of network config
- One time push of SSH key
- Full software install
ansible.cc
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15. Cloudera Manager...
Cloudera Manager used for
- Cluster install software.
- Currently manual labour, can be automated using
the API
cloudera.com
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16. Show me the code...
Add node information to the cobbler CMS
First make the install dvd known to cobbler:
mount -t iso9660 -o loop /<directoryname>/CentOS-6.4-x86_64-bin-DVD1.iso /mnt/dvd
cobbler import --path=/mnt/dvd --name=CentOS64
Next make the node information known:
sudo cobbler system add --name=node01 --profile=CentOS64-x86_64 --hostname=node01
--mac=<00:00:00:00:00:00> --ip-address=10.20.0.101 --static=True
If needed, re-enable the netboot flag:
sudo cobbler system edit --name=node01 --netboot-enabled=True
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17. Show me the code...
Ansible needs to know what goes where
[cluster]
node01
node02
node03
[cobbler]
cobbler
[proxy]
cobbler
[ganglia-master]
node01
[ganglia-nodes:children]
cluster
[cloudera-manager]
node01
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18. Show me the code...
For the rest it’s just a DSL thinghy with extra’s
- hosts:
- cloudera-manager
- cluster
user: root
sudo: yes
vars_files:
- vars/common.yml
tasks:
- include: cloudera-manager/tasks/common.yml
handlers:
- include: cloudera-manager/handlers/main.yml
- name: Configure CM4 Repo
copy: src=cloudera-manager/files/etc/yum.repos.d/cm4.repo dest=/etc/yum.repos.d/ owner=root
group=root
- name: Install CM4 common stuff
yum: name=$item state=installed
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19. Demo...
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20. Shared problems...
- No magic: Vendor specific hardware can screw
things up (strange names for disk mounts for
example)
- Bios settings, different RAID settings are not handled
(yet).
- Large amount of initial network traffic with large
clusters (N-times downloading the same software
packages from yum repositories) => Repo mirroring
to the rescue
- MAC address of all nodes must be known
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21. Take aways...
- Do automate from the start
- It’s easy
- Use (our) open source code to get a head start
https://github.com/godatadriven/ansible_cluster
- Our team will do the additional consultancy
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22. GoDataDriven
We’re hiring / Questions? / Thank you!
@krisgeus
krisgeusebroek@godatadriven.com
Kris Geusebroek
Big Data Hacker
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