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Start your training Virtual Machines

Please follow instructions to Start the Opal VMs.

Recall from the installation instructions, attempting to access the Opal web interface is a simple check to tell if the VMs have started:

• http://192.168.56.100:8080

• http://192.168.56.101:8080 

Login Dataframe

builder <- DSI::newDSLoginBuilder()
builder$append(server = "server1",  url = "http://192.168.56.100:8080/",
               user = "administrator", password = "datashield_test&", driver = "OpalDriver")
builder$append(server = "server2", url = "http://192.168.56.101:8080/",
               user = "administrator", password = "datashield_test&", driver = "OpalDriver")
 
logindata <- builder$build()

connections <- DSI::datashield.login(logins = logindata, assign = TRUE)

• Where can I find out what data I am looking at? The column names derived from ds.colnames() aren’t very descriptive!

  • This is what the data dictionary is for! In the tutorial for DataSHIELD above, we connect to the CNSIM dataset. The dictionaries are stored in the Opal server (which, for the tutorial, can be accessed at the IP address http://192.168.56.100:8080) , logging in with the username & password (as in the tutorial), and navigating:

    • from the homepage, select “Projects” 3rd from left on the top bar;

    • on the table of projects select the one you are interested in (e.g. CNSIM);

    • on the next page, select any of the studies in the table (usually all the same parameters) (e.g. CNSIM1);

    • on the next page the data dictionary is stored with descriptions of each variable.

• Why can I not connect to the data after starting my VM?

  • It often takes 2 minutes for your VM to start, longer if you are loading two VMs simultaneously. It also is dependent on your computer’s processor power and the available RAM. Please be patient if it is being slow, and check back after 5 minutes, your VMs should have powered up successfully and be ready for use!

• A ds._function_ has disappeared! DataSHIELD doesn’t recognise it exists! The help for it won’t load!

  • Try using devtools::check() to force RStudio to recognise it. To do this, you need to have the R Package “Devtools” installed. Instructions for installing it are on the CRAN. The installation does take 15 minutes, beware if you are under time pressure!