Administrator Guide

This Guide covers the installation, configuration, and maintenance of gCore.

Prerequisites

The following are prerequisite for the installation of gCore:

A platform compatible GT requirements.

J2SE 1.6 update 4 SDK or greater. Sun's reference implementation is recommended, but versions from IBM, HP, or BEA should work equally well.

Ant 1.6.5+ to build gCF sources or to develop services with it.

an SVN client to install gCore from the SVN repository.

GNU tar to install gCore from archived distributions.

sudo privileges on the shell.

The following are pre-requisites for the operation of gHN in any infrastructure:

A static IP address and preferably a DNS name.

The following are pre-requisites for the operation of gHN in a secure infrastructure:

A ntp server to synchronise the machine's clock for correct credential validation.

A host certificate and private key owned by the user that runs the container and stored in an arbitrary position on the machine: the paths must be set in the global security descriptor file, as described in GHN security configuration section. In the most of cases the certificate and the key are stored respectively in:

 /etc/grid-security/hostpubliccert.pem (please check that the certificate file has -rw-r--r-- permissions)
 /etc/grid-security/hostprivatekey.pem (please check that the private key file has -r-------- permissions).

The public keys of the certification authorities to be accepted by the GHN,owned by the user that runs the container and stored in:

/etc/grid-security/certificates (the permissions are -rw-r--r--)

for further information, please refer to gCube security configuration section.

Installation

Once downloaded, gCore can be installed in a directory of choice (the gCore location). In either case, proceed to the installation as a a non-privileged user with read and write permissions on the gCore location. Due to some technical constraints, the current version of gCore requires that different installations must run under different users, i.e. the same user cannot configure and execute more than one container.

The structure of the installation is the following:

|-bin
|
|-config
|
|-endorsed
|
|-etc
|
|-lib
|
|-libexec
|
|-logs
|
|-share

Some folders are of immediate interest to administrators and developers alike:

`bin`	executables.
`config`	gHN configuration files.
`etc`	configuration files of container's and deployed service.
`lib`	standard and deployed service libraries.
`logs`	Log files for gHN, Local Services, and legacy technologies.
`share`	build tools, standard and deployed service interfaces and schemas.

gHN Yum Repositories

Starting from gcube 2.5.0, the gHN container is distributed, along with the usual tar.gz format, in rpm packages in order to facilitate the installation on platforms that supports rpm packaging system. For each release a YUM repository is created containing all rpm packages needed to successfully install a gHN node.

Targeted platforms are, for the moment, CERN Scientific Linux 4 32/64 bits and CERN Scientific Linux 5 32/64 bits.

Installation procedure:

go to the distribution site and download the .repo file for the gHN version.

cd /etc/yum.repos.d
wget <DISTRIBUTION_SITE_LINK>

the content of the downloaded file should be similar to this:

[ghn2-3-0]
name=D4Science gHN version 2-3-0
baseurl=http://etics-repository.cern.ch/repository/pm/volatile/repomd/id/064dc458-c5b5-4836-8d20-b0baaedf46ff/sl5_x86_64_gcc412
enabled=1

to install the gHN software, issue:

yum install org.gcube.distribution.ghn-rpm-distribution --nogpgcheck

Third-party software

gCore ships a number of third party products. The source material is copyright of the original publishers and software are governed by the terms and conditions of the third-party software.

Here it is a complete list grouped by provider.

Apache Software Foundation (AFS) ANT

ant-launcher 1.6.5
ant 1.6.5
antlr 2.7.6

ASF AXIS

addressing 1.0
axis 1.2RC (globus patched)
saaj 1.2RC
jaxrpc 1.2RC
axis-url 1.2.6
wsdl4j 1.2RC

ASF XML

resolver 1.1.1
xercesImpl 2.6.2
xml-apis 2.6.2
xmlsec 1.2.1
xalan 2.6

ASF COMMONS

commons-beanutils 1.6.1
commons-cli 2.0
commons-collections 3.0
commons-digester 1.2
commons-discovery 0.2dev
commons-io 1.2
commons-lang 2.4
commons-logging 1.1.1

Tomcat 4.1

naming-java 4.1
naming-resources 4.1
naming-factory 4.1
naming-common 4.1

GLOBUS 4.0.x

cog-axis
cog-jglobus
cog-tomcat
cog-url
puretls 0.9b4
cryptix-asn1 ?
cryptix.jar ?
cryptix32 3.2.0
bootstrap ?,
globus_usage_core
globus_usage_packets_common
globus_wsrf_mds_aggregator
globus_wsrf_mds_aggregator_stubs
globus_wsrf_servicegroup
globus_wsrf_servicegroup_stubs,
wsrf_common
wsrf_core
wsrf_mds_index_stubs
wsrf_mds_usefulrp
wsrf_test
wsrf_tools
wsrf_mds_usefulrp_schema_stubs
wsrf_provider_jce
wsrf_core_stubs
wsrf_mds_index

gLite

glite-security-util-java 1.3.4

MISC

cglib 2.2
objenesis 1.1
bcprov-jdk14 1.2.2
jce-jdk13 1.2.5
concurrent ?
SUN servlet.jar 2.3/1.2(JSP)
opensaml 1.0.1 (globus patched)
kxml2 2.3.0
log4j 1.2.15
jgss ?
junit 3.8.1
wss4j ?
SUN jsr173_api ?
BEA commonj 1.1
Jaxen XPath library - jaxen-1.1-beta-9.jar

Configuration

Configuring the installation can be roughly distributed across the following steps: configuring the environment, the container, the gHN associated with a running instance of the container, and the operation of the gHN in a secure infrastructure.

Configuring the Environment

Define an environment variable GLOBUS_LOCATION and point it to the gCore location. Assuming a bash shell:

export GLOBUS_LOCATION=absolute path to your gCore location

(optional) Add $GLOBUS_LOCATION/bin to the value of your PATH environment variable.:

export PATH=$PATH:$GLOBUS_LOCATION/bin

(optional) If building gCF-compliant services, define an environment variable BUILD_LOCATION and set it to the location from which ant will be invoked and where temporary build structures and artefacts will be located:

export BUILD_LOCATION=absolute path to your build location

Configuring the Container

Specify the hostname of your machine as the value of logicalHost parameter in the container's configuration file $GLOBUS_LOCATION/etc/globus_wsrf_core/server-config.wsdd:

<parameter name="logicalHost" value="..yourhostname..."/>

In the default configuration, the container typically allocates 1GB of heap space to the JVM in which it runs. This is a production-level requirement and can be increased by setting new parameters in the $GCORE_START_OPTIONS variable, either by editing the script $GLOBUS_LOCATION/bin/gcore-start-container or by adding it to the execution environment. If one wants to decrease the memory used, it is needed to edit the script, since, due to the Java Virtual Machine behavior, in case of duplicated setting, the higher setting is considered.

Moreover, any setting reported in the $GCORE_START_OPTIONS variable is passed to the container process and evaluated by the JVM.

Configuring the gHN

The configuration of the gHN that relates to its operation within the infrastructure and can be found in $GLOBUS_LOCATION/config/GHNConfig.xml. The file $GLOBUS_LOCATION/config/GHNConfig.client.xml can be used to dedicate a separate configuration to a gHN that operates in client mode.

The following gHN properties are available for configuration:

`securityenabled`	`true` if the gHN can operate in a secure infrastructure, `false` otherwise.
`mode`	either `CONNECTED` or `STANDALONE` depending on whether the gHN does or does not publish information in the infrastructure.
`infrastructure`	the name of the infrastructure in which the gHN operates. (e.g. `gcube`, `d4science`,...).
`startScopes`	a comma-separated list of VOs that the gHN joins.
`allowedScopes`	a comma-separated list of VOs that the gHN will potentially join (upon VO Manager decision).
`labels`	the name of the file that includes custom labels to characterize the gHN. These are added to those automatically derived by gCore and published in the gHN profile. The file name must be relative to the `$GLOBUS_LOCATION/config` directory.
`GHNtype`	either `DYNAMIC` or `STATIC` depending on whether the gHN can or cannot be used as a target for dynamic deployment operations.
`coordinates`	a pair of comma-separated values for the latitude and longitude of the gHN. Coordinates for some popular locations are available here.
`country`	the two-character ISO code of the Country where the gHN is located.
`location`	the name of the location.
`publishedHost`	the hostname to declare in the GHN and Running Instance profiles, if different from the actual one
`publishedPort`	the port to declare in the GHN and Running Instance profiles, if different from the actual one
`updateInterval`	how often the gHN must has to refresh its profile on the IS (in seconds).
`portRange` [optional]	a dash-separated pair of numbers that identify a range of free ports, if any.
`testInterval` [optional]	how often the monitoring Probes have to perform local test on the gHN

For example, the configuration required to join the gHN to the /gcube/devsec and /gcube/testing VOs is the following:

 infrastructure = gcube 
 startScopes = devsec,testing

For an in-depth coverage of scope and scope-related parameters (infrastructure and startScopes) see the Developer Guide.

Configuring Logging

A running gCore container will produce extensive logs in accordance with the log4j configuration directives container in $GLOBUS_LOCATION/container-log4j.properties. By default, the container logs in a file called $GLOBUS_LOCATION/logs/container.fulllog with a TRACE level for all the gCF components, and in $GLOBUS_LOCATION/logs/container.log with a INFO level for all the gCF components. Local Services have also dedicated file loggers.

Configuring Access Logs purging

Starting from GHN v 3.7.0, the GHN distribution contains a mechanism to clean access log files from the system ( that in some cases can occupy a considerable amount of space).

The script gcore-clean-accesslogs can be used to remove accesslogs older than 7 days ( configurable) and it can also be installed as cronjob via the gcore-clean-accesslogs-cron. Both files are located under the $GLOBUS_LOCATION/bin folder of the GHN.

In case of older versions of GHN distributions the files can be downloaded from:

and installed under the $GLOBUS_LOCATION/bin folder.

PLEASE NOTE : the scripts assume that the GLOBUS_LOCATION var is set inside the $HOME/.profile or $HOME/.bashrc

Configuring container security

//OUTDATED SECTION Detailed information about secure container configuration is provided in gCube security configuration section.

Detailed information about not default settings (for example, interoperability with secure external infrastructure or with a VOMS server, is availabled in Security Libraries section of gCube wiki. //END OF OUTDATED SECTION

Supporting resource encryption/decryption

If the gHN is foreseen to manage gCube encrypted resources, the AES symmetric key has to be downloaded and stored in the $GLOBUS_LOCATION/config folder.

Verify the Installation

To verify the installation, firstly start the container with the script $GLOBUS_LOCATION/bin/gcore-start-container in a not secure infrastructure, or $GLOBUS_LOCATION/bin/gcore-start-secure-container in a secure infrastructure. So, assuming PATH is set as recommended above:

gcore-start-container

or

gcore-start-secure-container

will suffice. Any instance of the container which is already running should be automatically kill-ed. By default, the commands above start the container on the port 8080 in a not secure infrastructure, 8443 in a secure infrastructure. To switch on another port, use the -p <port> option.

Then, two steps can be performed to verify that the container is locally working fine:

the new instance should log the list of deployed services in $GLOBUS_LOCATION/nohup.out <code> and detailed information about the startup of local services in <code>$GLOBUS_LOCATION/logs/container.log. Lack of visible errors in both files indicates a successful gCore installation and startup.
stopping the container, which is an action that contacts the container itself. For this, use the appropriate stop command, according to your configuration:

gcore-stop-container

or

gcore-stop-secure-container

Finally, for a full exploitation of the container (e.g. remote management and deployment, and having your services contacted), the host and port must be public and reachable from outside.

Troubleshooting

gHN with a high number of invocations

If a gHN hosts a service instance subjects to a high number of invocations, it might happen that the gContainer stops to serve callers' requests. This is due to mistaken usage of the "id" command of the underlying technology. Soon, the process will fall into a "too many files open" state and it basically does nothing from that moment on.

When such a condition is predictable, we suggest to create a temporary folder for the system commands, remove the "id" command from there and use that folder in the PATH instead the "official" one.

The complete workaround is the following:

create a folder where to collect the system commands:

mkdir fakebin
cd fakebin
find /usr/bin -type f -exec ln  {}  \;
find /usr/bin -type l -exec cp -a {} . \;
rm id

remove the /usr/bin folder from the PATH

add the new fakebin folder to the PATH

Of course, this could have impact on the other processes, therefore the new patched environment must be used only for the gContainer process.