Rootd @ CCALI


I experiences issues trying to get rootd working at CCALI. I could contact the user support but I couldn’t find any help googling on these error messages so I think anyway this topic may be helpful for others.

I am willing to access remotely to some rootfiles which are hosted on a CCALI (CCIN2P3, Lyon) machine. So I log into the CCALI machine and type

which seems to work. However, trying to access a file lead to the following errors :

$ root -l root [0] TFile *f = TFile::Open("root://","new") Error in <TXNetSystem::Connect>: some severe error occurred while opening the connection at root:// - exit Error in <TXNetSystem::TXNetSystem>: fatal error: connection creation failed. Error in <TXNetFile::CreateXClient>: open attempt failed on root://

Should I understand that CCALI forbids the use of rootd ?

Edit : After some tests on another (non CCALI) machine I figured out that this error occurs when you try to connect to a port where rootd is not listening or when the port where rootd is listening is filtered by the router. I guess this is what happens here.

Maybe these error messages could be make a bit more clear about that.

Dear berder,

Yes, the ports where the daemons are expected to listen must be accessible from outside, i.e. not filtered out by the firewall.

The problem is that the client does not have such information: the only thing that it knows is the the connection cannot be open.

G. Ganis

Ok. So for the records, if anyone finds this topic while looking for the error messages, I advice to check that the port is opened with nmap. In the previous example :