sysctl -a
sysctl -A
sysctl mib
sysctl net.ipv4.conf.all.rp_filter

result:

abi.vsyscall32 = 1
debug.exception-trace = 1
debug.kprobes-optimization = 1
dev.cdrom.autoclose = 1
dev.cdrom.autoeject = 0
dev.cdrom.check_media = 0
dev.cdrom.debug = 0
dev.cdrom.info = CD-ROM information, Id: cdrom.c 3.20 2003/12/17
dev.cdrom.info =
dev.cdrom.info = drive name:            sr0
dev.cdrom.info = drive speed:           48
dev.cdrom.info = drive # of slots:      1