We need a text file containing the login information of the servers to visit. Choose a file name to taste, call it SV.fil, or, as I did, svctl (~ "server control"). No "extension" (remainder from MSDOS times) needed. As I can see, you already added your local host for ease of operation.



Yes,cat copies its stdin (or the files given as arguments) to stdout - that was just for showing readers the contents of that file.


In the while loop, we're reading the server info line by line into the SV variable, then execute a "compound command" consisting of two reads to populate two arrays' elements indexed by the CNT variable which in turn is pre-incremented once per loop, so both arrays are indexed by the same value. stdin of this compound command is redirected from a "here string", consisting of a "command substitution" $(...) that provides the stdout of the entire ssh command including the two stat commands executed on the remore node for the two target files.



With four servers in the control file, we should end up with eight file sizes, four for file1 and four for file2, in arrays FILESZ1 and FILESZ2, indexed 1 ... 4 (given CNT was unset or reset to 0 upfront). You now can work on those array elements, as you did before, like

Code:

if [ ${FILESZ1[1]} -eq ${FILESZ1[2]} ]; then

. You could do it e.g. in a for loop 2 ... 4 to improve efficiency and readability.