11.4. IPv6-related entries in /proc/net/

In /proc/net there are several read-only entries available. You cannot retrieve information using ”sysctl” here, so use e.g. ”cat”.

11.4.1. if_inet6

Here all configured IPv6 addresses are shown in a special format. The example displays for loopback interface only. The meaning is shown below (see ”net/ipv6/addrconf.c” for more).

# cat /proc/net/if_inet6
00000000000000000000000000000001 01 80 10 80 lo
+------------------------------+ ++ ++ ++ ++ ++
|                                |  |  |  |  |
1                                2  3  4  5  6

  1. IPv6 address displayed in 32 hexadecimal chars without colons as separator

  2. Netlink device number (interface index) in hexadecimal (see ”ip addr” , too)

  3. Prefix length in hexadecimal

  4. Scope value (see kernel source ” include/net/ipv6.h” and ”net/ipv6/addrconf.c” for more)

  5. Interface flags (see ”include/linux/rtnetlink.h” and ”net/ipv6/addrconf.c” for more)

  6. Device name

11.4.2. ipv6_route

Here all configured IPv6 routes are shown in a special format. The example displays for loopback interface only. The meaning is shown below (see ”net/ipv6/route.c” for more).

# cat /proc/net/ipv6_route
00000000000000000000000000000000 00 00000000000000000000000000000000 00
+------------------------------+ ++ +------------------------------+ ++
|                                |  |                                |
1                                2  3                                4

¬ 00000000000000000000000000000000 ffffffff 00000001 00000001 00200200 lo
¬ +------------------------------+ +------+ +------+ +------+ +------+ ++
¬ |                                |        |        |        |        |
¬ 5                                6        7        8        9        10

  1. IPv6 destination network displayed in 32 hexadecimal chars without colons as separator

  2. IPv6 destination prefix length in hexadecimal

  3. IPv6 source network displayed in 32 hexadecimal chars without colons as separator

  4. IPv6 source prefix length in hexadecimal

  5. IPv6 next hop displayed in 32 hexadecimal chars without colons as separator

  6. Metric in hexadecimal

  7. Reference counter

  8. Use counter

  9. Flags

  10. Device name

11.4.3. sockstat6

Statistics about used IPv6 sockets. Example:

# cat /proc/net/sockstat6
TCP6: inuse 7 
UDP6: inuse 2 
RAW6: inuse 1 
FRAG6: inuse 0 memory 0

11.4.4. tcp6

To be filled.

11.4.5. udp6

To be filled.

11.4.6. igmp6

To be filled.

11.4.7. raw6

To be filled.

11.4.8. ip6_flowlabel

To be filled.

11.4.9. rt6_stats

To be filled.

11.4.10. snmp6

SNMP statistics, can be retrieved via SNMP server and related MIB table by network management software.

11.4.11. ip6_tables_names

Available netfilter6 tables