Book Image

Ceph: Designing and Implementing Scalable Storage Systems

By : Michael Hackett, Vikhyat Umrao, Karan Singh, Nick Fisk, Anthony D'Atri, Vaibhav Bhembre
Book Image

Ceph: Designing and Implementing Scalable Storage Systems

By: Michael Hackett, Vikhyat Umrao, Karan Singh, Nick Fisk, Anthony D'Atri, Vaibhav Bhembre

Overview of this book

This Learning Path takes you through the basics of Ceph all the way to gaining in-depth understanding of its advanced features. You’ll gather skills to plan, deploy, and manage your Ceph cluster. After an introduction to the Ceph architecture and its core projects, you’ll be able to set up a Ceph cluster and learn how to monitor its health, improve its performance, and troubleshoot any issues. By following the step-by-step approach of this Learning Path, you’ll learn how Ceph integrates with OpenStack, Glance, Manila, Swift, and Cinder. With knowledge of federated architecture and CephFS, you’ll use Calamari and VSM to monitor the Ceph environment. In the upcoming chapters, you’ll study the key areas of Ceph, including BlueStore, erasure coding, and cache tiering. More specifically, you’ll discover what they can do for your storage system. In the concluding chapters, you will develop applications that use Librados and distributed computations with shared object classes, and see how Ceph and its supporting infrastructure can be optimized. By the end of this Learning Path, you'll have the practical knowledge of operating Ceph in a production environment. This Learning Path includes content from the following Packt products: • Ceph Cookbook by Michael Hackett, Vikhyat Umrao and Karan Singh • Mastering Ceph by Nick Fisk • Learning Ceph, Second Edition by Anthony D'Atri, Vaibhav Bhembre and Karan Singh
Table of Contents (27 chapters)
Title Page
About Packt
Contributors
Preface
Index

Logs


Ceph performs extensive logging. Ceph can be configured to log directly through the central syslog or rsyslog service, but by default, it writes to local files. These are managed by the stock Linux logrotate facility. Here's the default rotation stanza that the Ceph Jewel release installs.

# cat /etc/logrotate.d/ceph.logrotate/var/log/ceph/*.log {    rotate 7    daily    compress    sharedscripts    postrotate        killall -q -1 ceph-mon ceph-mds ceph-osd ceph-fuse radosgw   
            || true    endscript    missingok    notifempty    su root ceph}

The default retention is 7 days, which this author at times finds to be too short. To increase to four weeks, replace the 7 with 30, but be careful that the filesystem where /var/log lives has adequate free space. As we note later in this chapter, Ceph logs can become quite large at times, and modestly-provisioned systems experience filled filesystems. To mitigate the risk of logjams (clogged logs?) it may be expedient to also add a maxsize...