data talk:Dcache/195/server/test/notes

Testing installed dCache system

• dCache web interface

If everything is right configured and running, you may try to call the web interface of your dCache instance inside a browser with the generic adress http://dcache-headnode.yourDomain:2288. For the dCache reference installation this looks like http://dgiref-dcache.fzk.de:2288 and can be viewed here: D-Grid dCache reference installation web interface.

• accessing file system with standard commands

[root@dgiref-dcache ~]# ls /pnfs/fzk.de/data/dgtest/
[root@dgiref-dcache ~]# touch /pnfs/fzk.de/data/dgtest/test.blub
[root@dgiref-dcache ~]# ls /pnfs/fzk.de/data/dgtest/
test.blub
[root@dgiref-dcache ~]# rm /pnfs/fzk.de/data/dgtest/test.blub
rm: remove regular empty file `/pnfs/fzk.de/data/dgtest/test.blub'? y
[root@dgiref-dcache ~]# ls /pnfs/fzk.de/data/dgtest/

[root@dgiref-dcache ~]# cp /bin/bash /pnfs/fzk.de/data/dgtest/test.blub
cp: closing `/pnfs/fzk.de/data/dgtest/test.blub': Input/output error

• copying data using dCache protocols

Use a UI-server and voms-proxies! (dgiref-login.fzk.de)

[user@dgiref-login]$ dccp /bin/bash gsidcap://dgiref-dcache.fzk.de:22128/pnfs/fzk.de/data/dgtest/testbin-1
Error ( POLLIN POLLERR POLLHUP) (with data) on control line [3]
Failed to create a control line
Error ( POLLIN POLLERR POLLHUP) (with data) on control line [5]
Failed to create a control line
Failed open file in the dCache.
Can't open destination file : Server rejected "hello"
System error: Input/output error

[user@dgiref-login]$ voms-proxy-info

Couldn't find a valid proxy.

[user@dgiref-login]$ voms-proxy-init -voms dgtest
Cannot find file or dir: /home/site/user/.glite/vomses
Enter GRID pass phrase:
Your identity: /C=DE/O=GermanGrid/OU=FZK/CN=user
Creating temporary proxy ................................................... Done
Contacting  dgrid-voms.fzk.de:15000 [/O=GermanGrid/OU=FZK/CN=host/dgrid-voms.fzk.de] "dgtest" Done
Creating proxy ...................................... Done
Your proxy is valid until Mon Nov 10 23:26:03 2008

[user@dgiref-login]$ voms-proxy-info
subject   : /C=DE/O=GermanGrid/OU=FZK/CN=user/CN=proxy
issuer    : /C=DE/O=GermanGrid/OU=FZK/CN=user
identity  : /C=DE/O=GermanGrid/OU=FZK/CN=user
type      : proxy
strength  : 512 bits
path      : /tmp/x509up_u10824
timeleft  : 11:59:58

Now you can copy data into dCache (using GSIdcap):

[user@dgiref-login]$ dccp /bin/bash gsidcap://dgiref-dcache.fzk.de:22128/pnfs/fzk.de/data/dgtest/testbin-1
Command failed!
Server error message for [1]: "no such file or directory /pnfs/fzk.de/data/dgtest/testbin-1" (errno 10001).
585908 bytes in 0 seconds

[user@dgiref-login]$ dccp /bin/bash gsidcap://dgiref-dcache.fzk.de:22128/pnfs/fzk.de/data/dgtest/testbin-1
Command failed!
Server error message for [2]: "File is readOnly" (errno 1).
Failed open file in the dCache.
Can't open destination file : "File is readOnly"
System error: Input/output error

[user@dgiref-login]$ dccp /bin/bash gsidcap://dgiref-dcache.fzk.de:22128/pnfs
/fzk.de/data/textgrid/testbin-1
Command failed!
Server error message for [1]: "no such file or directory /pnfs/fzk.de/data/textgrid/testbin-1" (errno 10001).
Command failed!
Server error message for [2]: "Permission denied (Parent)" (errno 2).
Failed open file in the dCache.
Can't open destination file : "Permission denied (Parent)"
System error: Input/output error

For checking copy the file back and make a checksum:

[user@dgiref-login]$ dccp gsidcap://dgiref-dcache.fzk.de:22128/pnfs/fzk.de/data/dgtest/testbin-1 /tmp/testfilefromdCache
585908 bytes in 0 seconds

[user@dgiref-login]$ md5sum /bin/bash /tmp/testfilefromdCache 
dc4e36cfdf491029a67f4e317cab3151  /bin/bash
dc4e36cfdf491029a67f4e317cab3151  /tmp/testfilefromdCache

Same procedure with srmcp tool (using GridFTP protocol) (also known as "srm put"):

[user@dgiref-login]$ srmcp file:////bin/bash gridftp://dgiref-dcache.fzk.de:2811/pnfs/fzk.de/data/dgtest/testbin-2
WARNING: SRM_PATH is defined, which might cause a wrong version of srm client to be executed
WARNING: SRM_PATH=/opt/d-cache/srm

And again fetching the file from dCache ("srm get"). Unfortunately dCache in the D-Grid reference installation only supports srm put in stream mode, which means, transfering data with only one single stream (normally up to ten). The reason for this is unknown and has to be investigated.

[user@dgiref-login]$ srmcp -debug=true -streams_num=1 \
> gridftp://dgiref-dcache.fzk.de:2811/pnfs/fzk.de/data/dgtest/testbin-2 file:////dev/null
WARNING: SRM_PATH is defined, which might cause a wrong version of srm client to be executed
WARNING: SRM_PATH=/opt/d-cache/srm

• Deleting files in dCache

Easiest is to delete the namespace entry:

[root@dgiref-dcache ~]# rm /pnfs/fzk.de/data/dgtest/testbin-1
rm: remove regular empty file `/pnfs/fzk.de/data/dgtest/testbin-1'? y

File will disapear (not immediate but) short after so dCache can prioritize read actions over deleting.

Regular users can delete files from the UI with srmrm (equals srm -rm):

[user@dgiref-login]$  srmrm srm://dgiref-dcache.fzk.de:8443/pnfs/fzk.de/data/dgtest/testbin-1
WARNING: SRM_PATH is defined, which might cause a wrong version of srm client to be executed
WARNING: SRM_PATH=/opt/d-cache/srm

GUI pcells for dCache

The core mechanism for administrating a dCache instance is the admin interface. This is a service you may connect to using a ssh client. Using the admin interface, you may communicate with the various components making up dCache, query their status and update their behaviour. Although dCache is a distributed system, you only ever connect to a single node; dCache will route your messages internally. The source for pcells, a graphical user interface which greately simplifys working with the admin interface, as well as an installation guide can be found at dCache.org. Once pcells is installed, this are the steps to take in order to connect to your dCache system:

1. start pcells and open new session
2. adjust settings by clicking on Setup
   1. addresses

      hostname = dCache_headnode.yourDomain

3. login as admin with (default) passphrase dickerel

Of course no one is forced to use this GUI but can still access the admin interface with a plain ssh client:

ssh -1 -c blowfish -p 2223 -l admin dCache_headnode.yourDomain

Guidance on how to use the admin interface is out of the scope of this documentation. Please look into the wiki at dCache.org.