add redo log member and increase log buffer in oracle RAC 11.2.0.4

ORACLE DB= 11.2.0.4

DB size = 55TB

NODES = 5

RAC/ASM

OS: Linux 6

we are getting this error in the alert log, "All online logs need archiving -    Examine archive trace files for archiving errors"

REQUEST: need syntax to add new redo log member and increase log buffer in our 11.2.0.4 - 5 Nodes RAC DB.

Query in GV$LOG for each instance.

INST_ID    GROUP#    THREAD#     BYTES

1                   1              1                    2,147,483,648

1                   2              1                    2,147,483,648

1                   3              2                    2,147,483,648

1                   4              2                    2,147,483,648

1                   5              3                    2,147,483,648

1                   6              3                    2,147,483,648

1                   7              4                    2,147,483,648

1                   8              4                    2,147,483,648

1                   9              5                    2,147,483,648

1                  10              5                    2,147,483,648

Thank you.