The info-provider takes as much information as possible from
dCache. To achieve this, it needs the internal
info, to be running and a
means to collect that information:
httpd. Make sure that
info services are running
within your dCache instance. By default, the
service is started on the admin-node; but it is possible to
configure dCache so it runs on a different node. You should
run only one
info service per dCache instance.
The traditional (pre-1.9.7) allocation of services to domains
info cell running in the
infoDomain domain. A
dCache system that has been migrated from this old
configuration will have the following fragment in the node’s
It is also possible to run the
info service inside a
domain that runs other services. The following example show the
information domain that hosts the
[information] [information/admin] [information/httpd] [information/topo] [information/info]
For more information on configuring dCache layout files, see the section called “Defining domains and services”.
Use the dcache services command to see if a
particular node is configured to run the
The following shows the output if the node has an
information domain that is configured to run the
/opt/d-cache/bin/dcache services | grep infoinformation info info /var/log/dCache/information.log
If a node has no domain configured to host the
service then the above dcache services
command will give no output:
/opt/d-cache/bin/dcache services | grep info
If no running domain within any node of
your dCache instance is running the
info service then
you must add the service to a domain and restart that domain.
In this example, the
info service is added to the
example domain. Note that the specific choice of
example) is just to give a concrete example;
the same process may be applied to a different domain.
The layouts file for this node includes the following
definition for the
[example] [example/admin] [example/httpd] [example/topo]
By adding the extra line
to the layouts file, in future, the
domain will host the
[example] [example/admin] [example/httpd] [example/topo] [example/info]
To actually start the
info cell, the
example domain must be restarted.
/opt/d-cache/bin/dcache restart exampleStopping example (pid=30471) 0 done Starting example done
example domain restarted, the
service is now running.
You can also verify both the
services are running using the wget command.
The specific command assumes that you are logged into the node
that has the
httpd service (by default, the admin node).
You may run the command on any node by replacing
localhost with the hostname of
the node running the
The following example shows the output from the
wget when the
info service is running
wget -O/dev/null http://localhost:2288/info--17:57:38-- http://localhost:2288/info Resolving localhost... 127.0.0.1 Connecting to localhost|127.0.0.1|:2288... connected. HTTP request sent, awaiting response... 200 Document follows Length: 372962 (364K) [application/xml] Saving to: `/dev/null' 100%[=========================================================================== ===>] 372,962 --.-K/s in 0.001s 17:57:38 (346 MB/s) - `/dev/null' saved [372962/372962]
httpd service isn’t running then the command will
generate the following output:
wget -O/dev/null http://localhost:2288/info--10:05:35-- http://localhost:2288/info => `/dev/null' Resolving localhost... 127.0.0.1 Connecting to localhost|127.0.0.1|:2288... failed: Connection refused.
To fix the problem, ensure that the
httpd service is
running within your dCache instance. This is the service that
provides the web server monitoring within dCache. To enable
the service, follow the same procedure for enabling the
info cell, but add the
httpd service within one of
the domains in dCache.
If running the wget command gives an error
Unable to contact the info cell. Please
ensure the info cell is running:
wget -O/dev/null http://localhost:2288/info--10:03:13-- http://localhost:2288/info => `/dev/null' Resolving localhost... 127.0.0.1 Connecting to localhost|127.0.0.1|:2288... connected. HTTP request sent, awaiting response... 503 Unable to contact the info cell. Pl ease ensure the info cell is running. 10:03:13 ERROR 503: Unable to contact the info cell. Please ensure the info cel l is running..
This means that the
info service is not running. Follow
the instructions for starting the
info service given