oracle log file at redhat 7.3

[pomin]

hi all, how I know where the log directory in oracle on redhat 7.3 ? because I have a problem with my server, I was installed redhat 7.3 and oracle 9.0.1 in Dell Power 2650. but after 2 week I get a problem is the computer "HANG". anyone can help me...... please I very appreciate     Regards,     Pomin