To verify if IPv6 is enabled or not, execute :<\/p>\n
1. Disable IPv6 in kernel module (requires reboot)<\/strong> 2. Regenerate a GRUB configuration file and overwrite existing one:<\/p>\n 3. Restart system and verify no line \u201cinet6\u201d in \u201cip addr show\u201d command output.<\/p>\n 2. Disable IPv6 using sysctl settings (no reboot required)<\/strong><\/p>\n 1. Append below lines in \/etc\/sysctl.conf:<\/p>\n 2. To make the settings affective, execute :<\/p>\n NOTE : make sure the file \/etc\/ssh\/sshd_config contains the line AddressFamily inet to avoid breaking SSH Xforwarding if you are using the sysctl method<\/p>\n 3. Add the AddressFamily line to sshd_config :<\/p>\n Restart sshd for changes to get get effect :<\/p>\n To verify if IPv6 is enabled or not, execute : # ifconfig -a | grep inet6 inet6 fe80::211:aff:fe6a:9de4 prefixlen 64 scopeid 0x20 inet6 ::1 prefixlen 128 scopeid 0x10[host] 1. Disable IPv6 in kernel module (requires reboot) 1. Edit \/etc\/default\/grub and add ipv6.disable=1 in line GRUB_CMDLINE_LINUX, e.g.: # cat \/etc\/default\/grub GRUB_TIMEOUT=5 GRUB_DEFAULT=saved GRUB_DISABLE_SUBMENU=true GRUB_TERMINAL_OUTPUT=”console” GRUB_CMDLINE_LINUX=”ipv6.disable=1 crashkernel=auto\u2026 Read More »<\/a><\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-981","post","type-post","status-publish","format-standard","hentry","category-tutorial"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/posts\/981","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/comments?post=981"}],"version-history":[{"count":2,"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/posts\/981\/revisions"}],"predecessor-version":[{"id":983,"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/posts\/981\/revisions\/983"}],"wp:attachment":[{"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/media?parent=981"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/categories?post=981"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.whplus.com\/blog\/wp-json\/wp\/v2\/tags?post=981"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}# ifconfig -a | grep inet6
\n inet6 fe80::211:aff:fe6a:9de4 prefixlen 64 scopeid 0x20
\n inet6 ::1 prefixlen 128 scopeid 0x10[host]<\/code><\/p>\n
\n1. Edit \/etc\/default\/grub and add ipv6.disable=1 in line GRUB_CMDLINE_LINUX, e.g.:<\/p>\n# cat \/etc\/default\/grub
\nGRUB_TIMEOUT=5
\nGRUB_DEFAULT=saved
\nGRUB_DISABLE_SUBMENU=true
\nGRUB_TERMINAL_OUTPUT=\"console\"
\nGRUB_CMDLINE_LINUX=\"ipv6.disable=1 crashkernel=auto rhgb quiet\"
\nGRUB_DISABLE_RECOVERY=\"true\"<\/code><\/p>\n# grub2-mkconfig -o \/boot\/grub2\/grub.cfg<\/code><\/p>\n# shutdown -r now<\/code><\/p>\n# ip addr show | grep net6<\/code>
\n<\/p>\nnet.ipv6.conf.all.disable_ipv6 = 1
\nnet.ipv6.conf.default.disable_ipv6 = 1<\/code><\/p>\n# sysctl -p<\/code><\/p>\n# vi \/etc\/ssh\/sshd_config<\/code><\/p>\n....
\nAddressFamily inet
\n....<\/code><\/p>\n# systemctl restart sshd<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"