Scalla

Xrd Configuration Reference

(with olbd, xrootd, and rootd Protocols)

Andrew Hanushevsky

Stanford Linear Accelerator Center

28 February 2007

Scalla: Structured Cluster Architecture for Low Latency Access

©2004-2007 by the Board of Trustees of the Leland Stanford, Jr., University

All Rights Reserved

Produced under contract DE-AC02-76-SFO0515 with the Department of Energy

This code is available under a BSD-style license allowing minimally restricted use.

1 Introduction. 5

Security Considerations. 6

1.1 Files Created by xrootd. 6

1.2 Starting the xrootd Daemon. 7

1.2.1 Using the StartXRD Script to Start xrootd. 11

1.2.2 Using the StoptXRD Script to Stop xrootd. 14

2 Specifying Conditional Directives. 15

3 Common xrd Configuration Directives. 17

3.1 adminpath. 17

3.1.1 Administrative Interface. 18

3.2 allow.. 19

3.3 port 21

4 Esoteric xrd Configuration Directives. 23

4.1 buffers. 23

4.2 network. 24

4.3 protocol 25

4.4 sched. 27

4.5 timeout 29

4.6 trace. 31

5 xrootd Configuration Directives. 33

5.1 async. 33

5.2 chksum.. 36

5.3 export 37

5.4 fslib. 38

5.5 log. 39

5.6 monitor 41

5.7 prep. 43

5.8 redirect 45

5.9 seclib. 47

5.10 trace. 48

6 rootd Configuration Directives. 49

7 Monitoring Data Format 51

7.1 Monitor Map Message Format 53

7.1.1 Message Info Field. 53

7.2 Monitor Trace Message Format 55

8 Document Change History. 58

1 Introduction

This document describes the eXtended Request Daemon (xrd) configuration directives and the configuration options for two protocols that can be used with xrd: XRootd and rootd.

The xrd is a server that can dynamically support multiple TCP/IP application service layer protocols. It is designed to provide a high performance environment for application services. The xrd is a generalized daemon and it makes its primary decision on which protocol to support based on the name given to the executable. Currently, the following executable names are fully supported:

· xrootd for eXtended Root Daemon and related protocols.

Configuration directives for xrd come from a configuration file. The characters “xrd” must prefix each directive in the configuration file. This makes xrd directives compatible with many servers providing other support services (e.g., xrootd, oolb, security, etc.). For example:

Component	Purpose
xrd	Extended Request Daemon
acc	Access control (i.e., authorization)
odc	Open distribute clustering
ofs	Open file system coordinating acc, odc, & oss components
olb	Open Load Balancing
oss	Open storage system (i.e., file system implementation)
sec	Security authentication
xrootd