| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | .TH IP\-NETNS 8 "20 Dec 2011" "iproute2" "Linux" |
| 2 | .SH NAME |
| 3 | ip-netns \- process network namespace management |
| 4 | .SH SYNOPSIS |
| 5 | .sp |
| 6 | .ad l |
| 7 | .in +8 |
| 8 | .ti -8 |
| 9 | .B ip |
| 10 | .RI "[ " OPTIONS " ]" |
| 11 | .B netns |
| 12 | .RI " { " COMMAND " | " |
| 13 | .BR help " }" |
| 14 | .sp |
| 15 | .ti -8 |
| 16 | .BR "ip netns" " { " list " } " |
| 17 | |
| 18 | .ti -8 |
| 19 | .BR "ip netns" " { " add " | " delete " } " |
| 20 | .I NETNSNAME |
| 21 | |
| 22 | .ti -8 |
| 23 | .BR "ip netns exec " |
| 24 | .I NETNSNAME command ... |
| 25 | |
| 26 | .SH DESCRIPTION |
| 27 | A network namespace is logically another copy of the network stack, |
| 28 | with it's own routes, firewall rules, and network devices. |
| 29 | |
| 30 | By convention a named network namespace is an object at |
| 31 | .BR "/var/run/netns/" NAME |
| 32 | that can be opened. The file descriptor resulting from opening |
| 33 | .BR "/var/run/netns/" NAME |
| 34 | refers to the specified network namespace. Holding that file |
| 35 | descriptor open keeps the network namespace alive. The file |
| 36 | descriptor can be used with the |
| 37 | .B setns(2) |
| 38 | system call to change the network namespace associated with a task. |
| 39 | |
| 40 | The convention for network namespace aware applications is to look |
| 41 | for global network configuration files first in |
| 42 | .BR "/etc/netns/" NAME "/" |
| 43 | then in |
| 44 | .BR "/etc/". |
| 45 | For example, if you want a different version of |
| 46 | .BR /etc/resolv.conf |
| 47 | for a network namespace used to isolate your vpn you would name it |
| 48 | .BR /etc/netns/myvpn/resolv.conf. |
| 49 | |
| 50 | .B ip netns exec |
| 51 | automates handling of this configuration, file convention for network |
| 52 | namespace unaware applications, by creating a mount namespace and |
| 53 | bind mounting all of the per network namespace configure files into |
| 54 | their traditional location in /etc. |
| 55 | |
| 56 | .SS ip netns list - show all of the named network namespaces |
| 57 | .SS ip netns add NAME - create a new named network namespace |
| 58 | .SS ip netns delete NAME - delete the name of a network namespace |
| 59 | .SS ip netns exec NAME cmd ... - Run cmd in the named network namespace |
| 60 | |
| 61 | .SH EXAMPLES |
| 62 | |
| 63 | .SH SEE ALSO |
| 64 | .br |
| 65 | .BR ip (8) |
| 66 | |
| 67 | .SH AUTHOR |
| 68 | Original Manpage by Eric W. Biederman |