Dear friendly helpers,

I want to compare the last line and the 2.nd line from the bottom later with a calculation. The rest of the script is working. What is wrong with my solution?

I want to take the 2nd line from the bottom. And I do not know the command.
TAIL -2 is wrong because it takes the 2 bottom lines.
So I tried to take the 2 lines from the bottom with tail -2 and later the 1. line with head -1.

SIZE_SCR=`grep ^scr /rsi/logs/csc_summary_size_check.log | tail -1 | cut -d";" -f4 | cut -b1-3`
SIZE_VORHER_SCR=`grep ^scr /rsi/logs/csc_summary_size_check.log | tail -2 | cut -d";" -f4 | cut -b1-3 | head -1`

tail -2 <input.txt | head -1

Looks like you are using a regular expression with grep. (if ^ is part of data, escape the character )
Try using egrep and with quotes

SIZE_SCR=`egrep '^scr' /rsi/logs/csc_summary_size_check.log | tail -1 | cut -d";" -f4 | cut -b1-3`
SIZE_VORHER_SCR=`egrep '^scr' /rsi/logs/csc_summary_size_check.log | tail -2 | cut -d";" -f4 | cut -b1-3 | head -1`