человечность, устанавливающая системные переменные

Я пытаюсь защитить свой сервер как ниже системных переменных

net.ipv4.icmp_echo_ignore_all=1
# IP Spoofing protection
​net.ipv4.conf.all.rp_filter=1
​net.ipv4.conf.default.rp_filter=1
#Ignore ICMP broadcast requests
​net.ipv4.icmp_echo_ignore_broadcasts=1
# Disable source packet routing
​net.ipv4.conf.all.accept_source_route=0
​net.ipv6.conf.all.accept_source_route=0 
​net.ipv4.conf.default.accept_source_route=0
​net.ipv6.conf.default.accept_source_route=0
# Ignore send redirects
​net.ipv4.conf.all.send_redirects=0
​net.ipv4.conf.default.send_redirects=0
# Block SYN attacks
​net.ipv4.tcp_syncookies=1
​net.ipv4.tcp_max_syn_backlog=2048
​net.ipv4.tcp_synack_retries=2
​net.ipv4.tcp_syn_retries=5
# Log Martians
​net.ipv4.conf.all.log_martians=1
​net.ipv4.icmp_ignore_bogus_error_responses=1
# Ignore ICMP redirects
​net.ipv4.conf.all.accept_redirects=0
​net.ipv6.conf.all.accept_redirects=0
​net.ipv4.conf.default.accept_redirects=0 
​net.ipv6.conf.default.accept_redirects=0
# Ignore Directed pings
​net.ipv4.icmp_echo_ignore_all=1

Изображение:

Но я добираюсь, некоторая ошибка происходят, когда я применил правила.

sysctl: cannot stat /proc/sys/​net/ipv4/conf/all/rp_filter: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/default/rp_filter: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/icmp_echo_ignore_broadcasts: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/all/accept_source_route: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv6/conf/all/accept_source_route: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/default/accept_source_route: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv6/conf/default/accept_source_route: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/all/send_redirects: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/default/send_redirects: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/tcp_syncookies: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/tcp_max_syn_backlog: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/tcp_synack_retries: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/tcp_syn_retries: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/all/log_martians: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/icmp_ignore_bogus_error_responses: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/all/accept_redirects: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv6/conf/all/accept_redirects: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/conf/default/accept_redirects: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv6/conf/default/accept_redirects: No such file or directory
sysctl: cannot stat /proc/sys/​net/ipv4/icmp_echo_ignore_all: No such file or directory

Ошибочные изображения:

Здесь кошка-A/etc/sysctl.conf

net.ipv4.icmp_echo_ignore_all=1$
# IP Spoofing protection$
M-bM-^@M-^Knet.ipv4.conf.all.rp_filter=1$
M-bM-^@M-^Knet.ipv4.conf.default.rp_filter=1$
#Ignore ICMP broadcast requests$
M-bM-^@M-^Knet.ipv4.icmp_echo_ignore_broadcasts=1$
# Disable source packet routing$
M-bM-^@M-^Knet.ipv4.conf.all.accept_source_route=0$
M-bM-^@M-^Knet.ipv6.conf.all.accept_source_route=0$
M-bM-^@M-^Knet.ipv4.conf.default.accept_source_route=0$
M-bM-^@M-^Knet.ipv6.conf.default.accept_source_route=0$
# Ignore send redirects$
M-bM-^@M-^Knet.ipv4.conf.all.send_redirects=0$
M-bM-^@M-^Knet.ipv4.conf.default.send_redirects=0$
# Block SYN attacks$
M-bM-^@M-^Knet.ipv4.tcp_syncookies=1$
M-bM-^@M-^Knet.ipv4.tcp_max_syn_backlog=2048$
M-bM-^@M-^Knet.ipv4.tcp_synack_retries=2$
M-bM-^@M-^Knet.ipv4.tcp_syn_retries=5$
# Log Martians$
M-bM-^@M-^Knet.ipv4.conf.all.log_martians=1$
M-bM-^@M-^Knet.ipv4.icmp_ignore_bogus_error_responses=1$
# Ignore ICMP redirects$
M-bM-^@M-^Knet.ipv4.conf.all.accept_redirects=0$
M-bM-^@M-^Knet.ipv6.conf.all.accept_redirects=0$
M-bM-^@M-^Knet.ipv4.conf.default.accept_redirects=0$
M-bM-^@M-^Knet.ipv6.conf.default.accept_redirects=0$
# Ignore Directed pings$
M-bM-^@M-^Knet.ipv4.icmp_echo_ignore_all=1$
root@ubuntu-s-2vcpu-4gb-lon1-01:/etc#