Red Hat provides mission-critical software and services using an open source model. This includes operating systems, virtualization, storage, and middleware. Red Hat develops products using a participate, integrate, and stabilize process involving upstream open source projects and communities. Red Hat Enterprise Linux works well with NFS for storage, with NFS version 4 improving performance and NFS version 4.1 introducing parallel access for improved scalability.

1. Red Hat Enterprise Linux / NFS
Syed M Shaaf Klaus Oxdal
Solution Architect Partner and Alliances, Nordics
Red Hat Red Hat
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2. WHAT WE DO
We offer a range of mission-critical software and services covering:
IaaS/PaaS MIDDLEWARE OPERATING SYSTEM
VIRTUALIZATION STORAGE
HOW WE DO IT.
We develop everything using
THE BENEFITS.
an OPEN SOURCE model.
Flexibility
Shared development reduces Faster technology innovation
costs & accelerates innovation.
Better quality
Open collaboration offers
products that genuinely meet Better price & performance
customers' requirements.
Alignment to your needs
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3. PRODUCT PROCESS
PARTICIPATE 100,000+
PROJECTS We participate in & create upstream
projects.
We build & support open communities
around integrated projects.
INTEGRATE
We enable software & hardware
partners to participate at every stage
of development.
STABILIZE We commercialize these
innovations together with a rich
ecosystem of services & certifications.
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4. OUR CUSTOMERS
The largest global exchange
on the planet. The largest global distribution
system in the world.
We are pleased to offer supported enterprise-class Red Hat
Enterprise Linux on demand for our customers. A leading enterprise cloud
computing vendor.
Wherever you live, it is likely that several letters that you Red Hat has impressed us with its
have received have been read, coded, and processed for outstanding engineering capabilities
delivery by one of our systems using JBoss Enterprise and commitment to our strategic
Application Platform as the middleware foundation. alliance.
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5. Red Hat Enterprise Linux
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6. RED HAT ENTERPRISE LINUX 6
SCALABILITY
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7. RED HAT ENTERPRISE LINUX 6
SCALABILITY
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8. RED HAT ENTERPRISE LINUX 6
SCALABILITY
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9. RED HAT ENTERPRISE LINUX 6
COMMUNITY LEADERSHIP
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10. NFS
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11. NFS V4
● NFS version 3 most used! Why Change it??
Performance!
● Version 4 is now the default protocol version for
RHEL6
● IETF: RFC3530: http://tools.ietf.org/html/rfc3530
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12. NFS Version 4.0 – Noteworthy features
● Version 4 is a Stateful Protocol.
● Delegations
● Mandated Security
● Referrals
● Firewall Friendly (kinda!)
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13. NFS version 4 – Gotchas!
● “All My files are owned by NOBODY!!!”
● Idmapping: steved@redhat.com ==> 3606
● DNS problem 90% of the time
● 'Domain=' in /etc/idmapd.conf
● Mounting Legacy servers.
● Mount negotiation start at v4
● For Legacy server use /etc/nfsmount.conf mount
negotiation
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14. NFS version 4.1
● Sessions
● Session IDs
● Parallel NFS (pNFS)
● File Layout (NAS environment) - Netapp
● Block Layout
● Object Layout
● IETF: RFC5661
● http://tools.ietf.org/html/rfc5661
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15. NFS version 4.1 in RHEL
● RHEL6 Client
● Tech Preview in 6.2
● pNFS: File layouts only
● RHEL7 Client
● All layouts supported.
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16. NFS version 4.1 – Make it work!
● Enabling 4.1/pNFS on the client
● mount -o minorversion=1
● Does the server support pNFS
● nfs4filelayout_init: NFSv4 File Layout Driver
Registering..
● “pnfs=<layout>” in /proc/self/mountstats
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17. NFS version 4.2
● Labeled NFS
● Security contexts
● Server to Server Copy
● offload to server copy operation
● Sparse Files
● IETF: Internet-Draft
● http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion2-11
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18. 6.4 and some important
changes
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19. Operating system - IO
Operating System ( Kernel )
2:
1:
Buffers and Cache
Storage
Data
3:
Application
Data
Application
Cache/Buffer Pool
Data
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20. Operating system – Direct IO
Operating System ( Kernel )
2:
1:
Buffers and Cache
Storage
Data
Application
Data
Application
Cache/Buffer Pool
Data
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21. Direct IO with PNFS, is it useful?
● O_DIRECT patches into pnfs
● Access the storage directly. Why?
● Databases are a good candidate, when?
● All operations are done in block size multiples
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22. RED HAT ENTERPRISE LINUX 6
Slots and TCP window size
● Allow the number of available slots to grow with the
TCP window size.
● RHEL 6.3 dynamically allocates RPC slots up to the
sunrpc.tcp_max_slot_table_entries ( 65536)
● Previously the number of in-flight RPC requests was
limited to 128 (default 16). This affected the
performance of OLTP workloads when using the kernel
based NFS client.
● NFS 4.1 max session slots is set with the boot
parameter:
nfs.max_session_slots (do not set higher than above)
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23. References
● Steve Dickson
● http://people.redhat.com/steved/Summits/
● NFSv4.1 new features: Sessions, Parallel NFS (pNFS)
● http://www.iaps.com/nfsv4.1-new-features.html
● Parallel NFS (pNFS)
● http://www.pnfs.com/
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24. Thank you!
Syed M Shaaf Klaus Oxdal
Solution Architect Partner and Alliances, Nordics
Red Hat Red Hat
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