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public:lta_howto [2020-05-20 08:43] – [User Access] Reinoud Bokhorstpublic:lta_howto [2020-11-04 15:36] (current) Bernard Asabere
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 To access the LTA, go to: [[https://lta.lofar.eu|lta.lofar.eu]] To access the LTA, go to: [[https://lta.lofar.eu|lta.lofar.eu]]
  
-For background information and in case of problems, please refer to the [[public:lta_faq|Frequently Asked Questions]] page.+For background information and in case of problems, please refer to the [[:public:lta_faq|Frequently Asked Questions]] page.
  
 ====== Release Notes ====== ====== Release Notes ======
  
- +^Release^Description| 
-^ Release ^ Description ^ +|July 2018|1) All data is now searchable, not only released data or data of projects you're a member of. Note that for downloading data (staging) the proprietary restrictions still apply. \\ 2) All projects can now be selected by all users, not only by project members. This provides the means to filter data based on project. \\ 3) Cone search algorithm implemented based on the Haversine formula for angular distance calculation. The calculated angular distance to the reference coordinates is now displayed in the search results. \\ 4) Search keys: added "time resolution", "Frequency resolution" and "nr. of subbands per subband group", removed "sky model database" and strategy name"|
-| July 2018 | 1) All data is now searchable, not only released data or data of projects you're a member of. Note that for downloading data (staging) the proprietary restrictions still apply. \\ 2) All projects can now be selected by all users, not only by project members. This provides the means to filter data based on project.\\ 3) Cone search algorithm implemented based on the Haversine formula for angular distance calculation. The calculated angular distance to the reference coordinates is now displayed in the search results. \\ 4) Search keys: added "time resolution", "Frequency resolution" and "nr. of subbands per subband group", removed "sky model database" and strategy name" | +
  
 ====== User Access ====== ====== User Access ======
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 Please visit [[https://webportal.astron.nl/pwm/public/ForgottenPassword|https://webportal.astron.nl/pwm/public/ForgottenPassword]] to request a new one. Please visit [[https://webportal.astron.nl/pwm/public/ForgottenPassword|https://webportal.astron.nl/pwm/public/ForgottenPassword]] to request a new one.
-\\ \\  
  
 === Searching / retrieving data === === Searching / retrieving data ===
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 The LTA catalogue can be searched directly without needing any account. Access to all projects and search queries will return results of the entire catalogue because metadata are public for all LTA content. The LTA catalogue can be searched directly without needing any account. Access to all projects and search queries will return results of the entire catalogue because metadata are public for all LTA content.
  
-Staging and subsequent downloading of __**public**__  data always requires an account with LTA user access privileges. This automatically happens if you were a member of the original project proposal in Northstar/MoM. If you do not have an account yet, you can register with "[[https://lofar.astron.nl/useradministration/public/setUpUserAccount.do|Create account]]". LTA access privileges will need to be granted by Science Operations and Support. Please, __once you have created your account, submit a support request to the [[https://support.astron.nl/rohelpdesk|Radio Observatory helpdesk]] asking for LTA privileges stating clearly your username__.+Staging and subsequent downloading of __**public**__  data always requires an account with LTA user access privileges. This automatically happens if you were a member of the original project proposal in Northstar/MoM. If you do not have an account yet, you can register with "[[https://lofar.astron.nl/useradministration/public/setUpUserAccount.do|Create account]]". LTA access privileges will need to be granted by Science Data Centre Operations (SDCO). Please, __once you have created your account, submit a support request to the [[https://support.astron.nl/rohelpdesk|ASTRON helpdesk]] asking for LTA privileges stating clearly your username__.
  
-To stage and retrieve project-related data in the LTA which are __**proprietary**__  you need to have an account in [[https://lofar.astron.nl/mom3|MoM]] that is enabled for the archive and coupled with the projects of interest. To this aim you can request Science Operations & Support to be added to the list of co-authors of the project. When you send such a request, you must add the project's PI in cc. After Science Operations and Support adds you to the project, you might get an email asking you to set a new password in [[https://webportal.astron.nl/pwm/private/Login|ASTRON Web Applications Password Self Service]]. Please note that this will set a new password not just for the LTA //but for MoM (LOFAR/WSRT) and Northstar as well//.+To stage and retrieve project-related data in the LTA which are __**proprietary**__  you need to have an account in [[https://lofar.astron.nl/mom3|MoM]] that is enabled for the archive and coupled with the projects of interest. To this aim you can request SDCO to be added to the list of co-authors of the project. When you send such a request, you must add the project's PI in cc. After SDCO adds you to the project, you might get an email asking you to set a new password in [[https://webportal.astron.nl/pwm/private/Login|ASTRON Web Applications Password Self Service]]. Please note that this will set a new password not just for the LTA //but for MoM (LOFAR/WSRT) and Northstar as well//.
  
 Please read the [[https://old.astron.nl/radio-observatory/observing-proposals/lofar-data-policy/lofar-data-policy|LOFAR Data Policy]] for more information about //proprietary// vs //public// data. Please read the [[https://old.astron.nl/radio-observatory/observing-proposals/lofar-data-policy/lofar-data-policy|LOFAR Data Policy]] for more information about //proprietary// vs //public// data.
-\\ \\  
- 
 === Step-by-step guide to search and retrieve data === === Step-by-step guide to search and retrieve data ===
  
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       * use the 'show data' button to select the project and to show all data in it       * use the 'show data' button to select the project and to show all data in it
   * from the screen that follows, you should be able to either search / select / stage the data products   * from the screen that follows, you should be able to either search / select / stage the data products
- 
  
 ====== How to find data in the archive ====== ====== How to find data in the archive ======
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 The LTA menu, as shown below, gives access to the main functionality. The LTA menu, as shown below, gives access to the main functionality.
  
 +{{:public:lta_menu.png?900}}
  
-{{:public:lta_menu.png?900|}} +A search in the LTA catalogue can be initiated by clicking on the SEARCH DATA button on the menu. At this point a default basic search is setup, where users can select the data product type of interest and perform a cone search. An advanced search mode, with more advanced parameters per data type, can also be selected by clicking on the drop menu on the left side.
- +
-A search in the LTA catalogue can be initiated by clicking on the SEARCH DATA button on the menu. At this point a default basic search is setup, where users can select the data product type of interest and perform a cone search. An advanced search mode, with more advanced parameters per data type, can also be selected by clicking on the drop menu on the left side. +
  
 A "project" can be selected by clicking on the BROWSE PROJECTS button on the menu. This is particularly useful for project related searches, as well as for checking either public projects or user's co-author membership. At this stage several actions are allowed A "project" can be selected by clicking on the BROWSE PROJECTS button on the menu. This is particularly useful for project related searches, as well as for checking either public projects or user's co-author membership. At this stage several actions are allowed
-    * Click on the project name to view the project details and eventually select it. + 
-    * Use the 'search' button to select the project and go to the search page. Subsequent searches will then be done within that project. +  * Click on the project name to view the project details and eventually select it. 
-    * Use the 'show data' button to select the project and to show all data in it.+  * Use the 'search' button to select the project and go to the search page. Subsequent searches will then be done within that project. 
 +  * Use the 'show data' button to select the project and to show all data in it.
  
 === Finding Data === === Finding Data ===
  
-{{:public:lta_observations_2018.png?900|}}+{{:public:lta_observations_2018.png?900}}
  
 Depending on the search parameters, e.g., which data products were requested (observation, pipeline), lists of observations and/or pipelines will be returned (see observations example above). From this point there are several options: Depending on the search parameters, e.g., which data products were requested (observation, pipeline), lists of observations and/or pipelines will be returned (see observations example above). From this point there are several options:
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 To see whether observations or pipelines have data products in the LTA, look for the "Number of Correlated/BeamFormed DataProducts" column. These colums, as also a few others, can also be used to navigate to the relevant dataproducts. To see whether observations or pipelines have data products in the LTA, look for the "Number of Correlated/BeamFormed DataProducts" column. These colums, as also a few others, can also be used to navigate to the relevant dataproducts.
  
-Once you have a list of dataproducts on your screen, the "Release Date" will tell you when the data are available for public download. If data is public, or you are a member of the project you are looking in, the "checkbox" column will be selectable and staging can proceed. +Once you have a list of dataproducts on your screen, the "Release Date" will tell you when the data are available for public download. If data is public, or you are a member of the project you are looking in, the "checkbox" column will be selectable and staging can proceed. You can also hover with your mouse over the checkbox and get more information, like the size, location and checksums.
-You can also hover with your mouse over the checkbox and get more information, like the size, location and checksums+
- +
-There is a separate page with **[[lta_tricks|more detailed information]]** and advanced tricks to help you find and download your data. +
-You will find examples of how to **browse the archive with your own python script**.+
  
 +There is a separate page with **[[:public:lta_tricks|more detailed information]]** and advanced tricks to help you find and download your data. You will find examples of how to **browse the archive with your own python script**.
  
 ==== Unspecified Data/Process ==== ==== Unspecified Data/Process ====
  
-Some data has had problems somewhere in the automation and control part of the LOFAR software during observation or processing. Sometimes a few subbands might be affected, sometimes an entire observation. Science Operations and Support will check the data, (re)run things manually or fix things if needed and then archive the data. This does mean that the automation and control sometimes loses track of the files and the archiving process has no information beyond the Observation ID and filename itself. In such cases a few subbands or an entire observation might end up under "Unspecified Process". We do attempt to fix things at a later date, but that is not always feasible. If the files were archived, the data itself is usable. What is missing is the information that the LTA needs to properly label and query the data.+Some data has had problems somewhere in the automation and control part of the LOFAR software during observation or processing. Sometimes a few subbands might be affected, sometimes an entire observation. Science Data Centre Operations will check the data, (re)run things manually or fix things if needed and then archive the data. This does mean that the automation and control sometimes loses track of the files and the archiving process has no information beyond the Observation ID and filename itself. In such cases a few subbands or an entire observation might end up under "Unspecified Process". We do attempt to fix things at a later date, but that is not always feasible. If the files were archived, the data itself is usable. What is missing is the information that the LTA needs to properly label and query the data.
  
 If an Observation is missing, or is missing subbands, please check if it ended up under Unspecified. If an Observation is missing, or is missing subbands, please check if it ended up under Unspecified.
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 Once you have a list of dataproducts, observations or pipelines, you can use the check boxes to select which files you want to download. The first check box can be used to select or deselect all files or observations on a page. Once you have a list of dataproducts, observations or pipelines, you can use the check boxes to select which files you want to download. The first check box can be used to select or deselect all files or observations on a page.
  
-{{:public:lta_staging_1.png?900|}}+{{:public:lta_staging_1.png?900}}
  
 The LOFAR Archive stores data on magnetic tape. This means that it cannot be downloaded right away, but has to be copied from tape to disk first. This process is called 'staging'. The LOFAR Archive stores data on magnetic tape. This means that it cannot be downloaded right away, but has to be copied from tape to disk first. This process is called 'staging'.
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 When you have made your selection of files, click on //stage//. This shows you the following message. It means that a request has been sent to the LTA staging service to start retrieving the requested files from the tape and make them available on disk. You will get a confirmation e-mail, to acknowledge that your staging request was received and the process was queued. When the files are staged, you will get a notification email informing you that your data are ready for retrieval. When you have made your selection of files, click on //stage//. This shows you the following message. It means that a request has been sent to the LTA staging service to start retrieving the requested files from the tape and make them available on disk. You will get a confirmation e-mail, to acknowledge that your staging request was received and the process was queued. When the files are staged, you will get a notification email informing you that your data are ready for retrieval.
  
-{{:public:lta_howto_3.png?900|}}+{{:public:lta_howto_3.png?900}}
  
-The e-mail that you get when the staging on disk is complete gives you a list of files and has several attachments. Amongst them are two files ''html.txt'' and ''srm.txt'':+The e-mail that you get when the staging on disk is complete gives you a list of files and has several attachments. Amongst them are two files ''html.txt''  and ''srm.txt'':
  
-{{:public:lta_howto4.png|}}+{{:public:lta_howto4.png}}
  
-There are two different ways to download your files with these attachments: [[#HTTP Download|http]] and [[#SRM Download|srm]]+There are two different ways to download your files with these attachments: [[#http_download|http]] and [[#srm_download|srm]]
  
-We also attach plain lists of the files/SURLs that were scheduled for staging (in the confirmation mail), those that were successfully staged, and (if any) those that could not be staged (in the success / partial success notifications). +We also attach plain lists of the files/SURLs that were scheduled for staging (in the confirmation mail), those that were successfully staged, and (if any) those that could not be staged (in the success / partial success notifications).
  
 +=== Please take note of the following ===
  
-=== Please take note of the following ==== +  - Unless you have an extremely fast connection (10 Gbit/s or more), **it is in general advisable to stage no more than 5 TB at a time**  (see also point 4). At maximum efficiency a 1 Gbit/s connection will already take 12 hours to retrieve 5 TB of data, in practice it will often take quite a bit more.
- +
-  - Unless you have an extremely fast connection (10 Gbit/s or more), **it is in general advisable to stage no more than 5 TB at a time** (see also point 4). At maximum efficiency a 1 Gbit/s connection will already take 12 hours to retrieve 5 TB of data, in practice it will often take quite a bit more.+
   - On a 1 Gbit/s connection as a general rule of thumb, you should be able to retrieve data at about 100-500 GB/hour, especially if you try to retrieve 4-8 files concurrently. If you see speeds much lower than this, you might have some kind of network problem and should in general contact your IT staff.   - On a 1 Gbit/s connection as a general rule of thumb, you should be able to retrieve data at about 100-500 GB/hour, especially if you try to retrieve 4-8 files concurrently. If you see speeds much lower than this, you might have some kind of network problem and should in general contact your IT staff.
   - Staging the data from tape to disk might take quite a bit of time. In the large data centres that the LTA uses, the tape drives are shared with all users and requests are queued. This is not just users of LOFAR but large data other projects like the LHC. This might mean that it takes anywhere from a few hours to a day or more to stage a copy of your data from tape to disk.   - Staging the data from tape to disk might take quite a bit of time. In the large data centres that the LTA uses, the tape drives are shared with all users and requests are queued. This is not just users of LOFAR but large data other projects like the LHC. This might mean that it takes anywhere from a few hours to a day or more to stage a copy of your data from tape to disk.
-  - The amount of space available for staging data is limited although quite large. This space is however shared between all LOFAR LTA users. This includes LTA operations for buffering data from CEP to the LTA before it gets moved to tape. If many users are staging data at the same time, and/or LOFAR operations is transferring large amounts of data, the system might temporarily run low on disk space. You might then get a message that your request was only partially successful. In general the request will still finish 1-2 days later and we do monitor if requests don't get stuck and restart if needed. +  - The amount of space available for staging data is limited although quite large. This space is however shared between all LOFAR LTA users. This includes LTA operations for buffering data from CEP to the LTA before it gets moved to tape. If many users are staging data at the same time, and/or SDC operations is transferring large amounts of data, the system might temporarily run low on disk space. You might then get a message that your request was only partially successful. In general the request will still finish 1-2 days later and we do monitor if requests don't get stuck and restart if needed.
   - We strive to keep a copy of data that was staged on disk for 1-2 weeks so you have some time to download it. After that it might get removed to make space for more recent requests. The copy of the data on tape is only read and will still be available if you need to access the data again at a later stage but you might need to stage a copy to disk again.   - We strive to keep a copy of data that was staged on disk for 1-2 weeks so you have some time to download it. After that it might get removed to make space for more recent requests. The copy of the data on tape is only read and will still be available if you need to access the data again at a later stage but you might need to stage a copy to disk again.
-  - We are continuously trying to improve the reliability and speed of the available services. Please contact Science Operations and Support if you have any problems or suggestions for improvement. +  - We are continuously trying to improve the reliability and speed of the available services. Please contact SDCO if you have any problems or suggestions for improvement. 
-  - The data centres the LTA uses also have maintenance or small outages sometimes. Science Operations and Support can advice you if this is the case and when it is planned to end, if you are having trouble accessing data. In general this will not be at the same dates as the LOFAR stop days.+  - The data centres the LTA uses also have maintenance or small outages sometimes. SDCO can advice you if this is the case and when it is planned to end, if you are having trouble accessing data. In general this will not be at the same dates as the LOFAR stop days
 + 
 +==== Staging Transient Buffer Board (TBB) data ==== 
 + 
 +TBB data needs to be staged by hand. Please send a request at [[https://support.astron.nl/rohelpdesk|https://support.astron.nl/rohelpdesk]] to stage the data for you, specifying the filenames to be staged. To download the data, please follow the instruction under Download Data for proper authentication. Data will then be available for download using 
 +<file> 
 + 
 +wget --no-check-certificate https://lofar-download.grid.surfsara.nl/lofigrid/SRMFifoGet.py?surl=<filename>
 + 
 +The filename should start or be prepended with srm:// 
 + 
 +</file> 
 + 
 +You will need a valid LTA account to access this data. If the filename is very short, you can view (e.g. cat) it to view errors that have occured.
  
 ===== Download data ===== ===== Download data =====
  
-You can download your requested data with the files from your e-mail notification. +You can download your requested data with the files from your e-mail notification. There are different possibilities and tools to do this. If you're unsure, which one to use, please refer to the according [[:public:lta_faq#there_are_different_ways_to_download_which_one_is_the_best|FAQ Answer]].
-There are different possibilities and tools to do this. If you're unsure, which one to use, please refer to the according [[public:lta_faq#there_are_different_ways_to_download_which_one_is_the_best|FAQ Answer]].+
  
 ==== HTTP download ==== ==== HTTP download ====
  
-If you open ''html.txt'' this file contains a list of http links that you can feed to a unix commandline tool like ''wget'' or ''curl'' or even use in a browser.+If you open ''html.txt''  this file contains a list of http links that you can feed to a unix commandline tool like ''wget''  or ''curl''  or even use in a browser.
  
 For wget you can use the following command line: For wget you can use the following command line:
-  wget -i html.txt +<code> 
-This will download the files in ''html.txt'' to the current directory (option '-i' reads the urls from the specified file).+ 
 +wget -i html.txt 
 + 
 +</code> 
 + 
 +This will download the files in ''html.txt''  to the current directory (option '-i' reads the urls from the specified file).
  
 Preferrably, especially when downloading large files, you should also use option '-c'. This will continue unfinished earlier downloads instead of starting a fresh download of the whole file. (Make sure to first delete existing files that contain error messages instead of data, if you use this option): Preferrably, especially when downloading large files, you should also use option '-c'. This will continue unfinished earlier downloads instead of starting a fresh download of the whole file. (Make sure to first delete existing files that contain error messages instead of data, if you use this option):
-  wget -ci html.txt + 
 +<code> 
 +wget -ci html.txt 
 + 
 +</code>
  
 Do not set the username and password on the wget command line because this allows other users on the system to view them in the process list. Instead you should create a file ~/.wgetrc with two lines according to the following example: Do not set the username and password on the wget command line because this allows other users on the system to view them in the process list. Instead you should create a file ~/.wgetrc with two lines according to the following example:
-  user=lofaruser + 
-  password=secret+<code> 
 +user=lofaruser 
 +password=secret 
 + 
 +</code>
  
 Note: This is only an example, you have to edit the file and enter your own personal user name and password! Note: This is only an example, you have to edit the file and enter your own personal user name and password!
- +
 Set access authorizations of the .wgetrc file to user only so that the credentials are not exposed to anybody else, e.g.: Set access authorizations of the .wgetrc file to user only so that the credentials are not exposed to anybody else, e.g.:
-  chmod 600 .wgetrc+ 
 +<code> 
 +chmod 600 .wgetrc 
 + 
 +</code> 
 There is no easy way to have wget rename the files as part of the command directly. It does not accept the -O flag inside a file it gets with -i. You can either rename files afterward, e.g. using the following command: There is no easy way to have wget rename the files as part of the command directly. It does not accept the -O flag inside a file it gets with -i. You can either rename files afterward, e.g. using the following command:
-  find . -name "SRMFifoGet*" | awk -F %2F '{system("mv "$0" "$NF)}'+ 
 +<code> 
 +find . -name "SRMFifoGet*" | awk -F %2F '{system("mv "$0" "$NF)}' 
 + 
 +</code> 
 or add the -O option to each line in html.txt but then feed each line to wget separately like this: cat ''html.txt | xargs wget''. By default the html.txt file does not contain such options. or add the -O option to each line in html.txt but then feed each line to wget separately like this: cat ''html.txt | xargs wget''. By default the html.txt file does not contain such options.
  
 The following Python script will take care of renaming and untarring the downloaded files: The following Python script will take care of renaming and untarring the downloaded files:
- 
 <file> <file>
 +
 #M.C. Toribio #M.C. Toribio
 #toribio@astron.nl #toribio@astron.nl
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   print outname+' untarred.'   print outname+' untarred.'
 +
 </file> </file>
  
Line 204: Line 230:
 import sys import sys
 import glob import glob
- 
  
 # AUTHOR: J.B.R. OONK  (ASTRON/LEIDEN UNIV. 2015) # AUTHOR: J.B.R. OONK  (ASTRON/LEIDEN UNIV. 2015)
 # - changes LTA retrieval filename to standard filename # - changes LTA retrieval filename to standard filename
-# - run in the directory where LTA files are located  +# - run in the directory where LTA files are located
  
 # FILE DIRECTORY # FILE DIRECTORY
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   print 'finished rename of: ', newname   print 'finished rename of: ', newname
 +
 </file> </file>
  
 Note that wget does not overwrite existing files. If you use the continue option ('-c') it will append any missing parts to the existing file. If you don't use the continue option and there is a file present (e.g. from a stopped earlier download), wget creates a new file by appending a number (e.g., '.1') to the filename. Note that wget does not overwrite existing files. If you use the continue option ('-c') it will append any missing parts to the existing file. If you don't use the continue option and there is a file present (e.g. from a stopped earlier download), wget creates a new file by appending a number (e.g., '.1') to the filename.
  
-There are some small example links if you browse to [[https://lofar-download.grid.sara.nl/]] where you can test with for example the file1M (which is 1 MB) if your setup is correct.+There are some small example links if you browse to [[https://lofar-download.grid.sara.nl/|https://lofar-download.grid.sara.nl/]] where you can test with for example the file1M (which is 1 MB) if your setup is correct. 
 ==== SRM download ==== ==== SRM download ====
  
-If you open the file ''srm.txt'' this file contains a list of srm locations which you would feed to ''srmcp''. SRM is a GRID specific protocol that is currently supported for data at the SARA and Jülich locations. It is faster, especially if you have significantly more than 1 Gbit/s bandwidth. It requires a valid [[GRID certificate]] and installation of the [[GRID srm software installation|GRID srm software]]. NB There is an [[srmclientinstallation|alternative installation that does not require root privileges]]. Contact Science Operations and Support if you think you might need a GRID account but it can not be provided by your own institute. +If you open the file ''srm.txt''  this file contains a list of srm locations which you would feed to ''srmcp''. SRM is a GRID specific protocol that is currently supported for data at the SARA and Jülich locations. It is faster, especially if you have significantly more than 1 Gbit/s bandwidth. It requires a valid [[:public:grid_certificate|GRID certificate]] and installation of the [[:public:grid_srm_software_installation|GRID srm software]]. NB There is an [[:public:srmclientinstallation|alternative installation that does not require root privileges]]. Contact SDC Operations via __[[https://support.astron.nl/rohelpdesk|ASTRON helpdesk ]]__if you think you might need a GRID account but it can not be provided by your own institute. An example command line would be: 
-An example command line would be: +<code> 
-  srmcp -server_mode=passive -copyjobfile=srm.txt+ 
 +srmcp -server_mode=passive -copyjobfile=srm.txt 
 + 
 +</code> 
 to retrieve all requested files contained in srm.txt or e.g. to retrieve all requested files contained in srm.txt or e.g.
-  srmcp -server_mode=passive srm://lofar-srm.juelich.de:8443/pnfs/fz-jeulich.de/data/lofar/ops/projects/commissioning2012/file.tar file://///data/files/file.tar 
-to retrieve a single file. You need ''--server_mode=passive'' if you are behind a firewall or on an internal network. Omitting this option may result in improved transfer speed as it will attempt to use multiple streams when retrieving a file. An alternative strategy to improve the overall transfer speed is to run multiple srmcp requests in parallel, e.g. by splitting the provided srm.txt file and feeding the partial lists to separate srmcp commands.   
  
-If you do experience insufficient transfer speeds with srmcp, you may want to look into using srmcp with a [[public:srmclientinstallation#fnal_dcache_client_tools|globus-url-copy]] copy script.+<code> 
 +srmcp -server_mode=passive srm://lofar-srm.juelich.de:8443/pnfs/fz-jeulich.de/data/lofar/ops/projects/commissioning2012/file.tar file://///data/files/file.tar
  
 +</code>
  
 +to retrieve a single file. You need ''–server_mode=passive''  if you are behind a firewall or on an internal network. Omitting this option may result in improved transfer speed as it will attempt to use multiple streams when retrieving a file. An alternative strategy to improve the overall transfer speed is to run multiple srmcp requests in parallel, e.g. by splitting the provided srm.txt file and feeding the partial lists to separate srmcp commands.
 +
 +If you do experience insufficient transfer speeds with srmcp, you may want to look into using srmcp with a [[:public:srmclientinstallation#fnal_dcache_client_tools|globus-url-copy]] copy script.
  
 ===== Troubleshooting ===== ===== Troubleshooting =====
  
-  * There is a [[public:lta_faq|LTA FAQ page]] that should help with the common difficulties. +  * There is a [[:public:lta_faq|LTA FAQ page]] that should help with the common difficulties. 
 + 
 +\\ 
 + 
  • Last modified: 2020-05-20 08:43
  • by Reinoud Bokhorst