CentOS 7: minikube tunnel failed with "netstat: invalid option -- 'f'"

[zzzuzik]

minikube tunnel fails with:
netstat: invalid option -- 'f'

OS ver:

cat /etc/centos-release
CentOS Linux release 7.6.1810 (Core)

netstat ver:

 netstat --version
net-tools 2.10-alpha

deployed from the default: net-tools:
net-tools.x86_64 0:2.0-0.24.20131004git.el7

[zzzuzik]

netstat --help

usage: netstat [-vWeenNcCF] [<Af>] -r         netstat {-V|--version|-h|--help}
       netstat [-vWnNcaeol] [<Socket> ...]
       netstat { [-vWeenNac] -I[<Iface>] | [-veenNac] -i | [-cnNe] -M | -s [-6tuw] } [delay]

        -r, --route              display routing table
        -I, --interfaces=<Iface> display interface table for <Iface>
        -i, --interfaces         display interface table
        -g, --groups             display multicast group memberships
        -s, --statistics         display networking statistics (like SNMP)
        -M, --masquerade         display masqueraded connections

        -v, --verbose            be verbose
        -W, --wide               don't truncate IP addresses
        -n, --numeric            don't resolve names
        --numeric-hosts          don't resolve host names
        --numeric-ports          don't resolve port names
        --numeric-users          don't resolve user names
        -N, --symbolic           resolve hardware names
        -e, --extend             display other/more information
        -p, --programs           display PID/Program name for sockets
        -o, --timers             display timers
        -c, --continuous         continuous listing

        -l, --listening          display listening server sockets
        -a, --all                display all sockets (default: connected)
        -F, --fib                display Forwarding Information Base (default)
        -C, --cache              display routing cache instead of FIB
        -Z, --context            display SELinux security context for sockets

  <Socket>={-t|--tcp} {-u|--udp} {-U|--udplite} {-S|--sctp} {-w|--raw}
           {-x|--unix} --ax25 --ipx --netrom
  <AF>=Use '-6|-4' or '-A <af>' or '--<af>'; default: inet
  List of possible address families (which support routing):
    inet (DARPA Internet) inet6 (IPv6) ax25 (AMPR AX.25)
    netrom (AMPR NET/ROM) ipx (Novell IPX) ddp (Appletalk DDP)
    x25 (CCITT X.25)

[michal-franc]

Same issue when running

make integration

Linux Mint 18.3 Sylvia

netstat version

net-tools 1.60
netstat 1.43

[tstromberg]

Curious! The tunnel should probably be made to use ip route if possible on Linux, but it does work on my Debian machine:

$ netstat -nr -f inet
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
...
$ netstat --version
net-tools 2.10-alpha
Fred Baumgarten, Alan Cox, Bernd Eckenfels, Phil Blundell, Tuan Hoang, Brian Micek and others
+NEW_ADDRT +RTF_IRTT +RTF_REJECT +FW_MASQUERADE +I18N +SELINUX
AF: (inet) +UNIX +INET +INET6 +IPX +AX25 +NETROM +X25 +ATALK +ECONET +ROSE -BLUETOOTH
HW:  +ETHER +ARC +SLIP +PPP +TUNNEL -TR +AX25 +NETROM +X25 +FR +ROSE +ASH +SIT +FDDI +HIPPI +HDLC/LAPB +EUI64 

[zzzuzik]

@tstromberg
Looks like RedHat distros uses capital ‘-F’ instead of ‘-f’

[balopat]

I'll look into this - it seems to mee that for linux using route -n would be a better option. The output format from route -n is very similar to netstat -nr (same from tunnel's perspective) and the default IP family is inet4 for both netstat and route on linux (unlike on FreeBSD/OSX). I'm planning to switch to route -n in route_linux.go.
I'm wondering what would be the benefit of ip route over route -n as it actually has a different output format too? @tstromberg?

The output below is from a centos7 docker container:

[root@38b5b6e0df3e /]#  netstat -nr 
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
0.0.0.0         172.17.0.1      0.0.0.0         UG        0 0          0 eth0
172.17.0.0      0.0.0.0         255.255.0.0     U         0 0          0 eth0
[root@38b5b6e0df3e /]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         172.17.0.1      0.0.0.0         UG    0      0        0 eth0
172.17.0.0      0.0.0.0         255.255.0.0     U     0      0        0 eth0
[root@38b5b6e0df3e /]# ip route
default via 172.17.0.1 dev eth0 
172.17.0.0/16 dev eth0 proto kernel scope link src 172.17.0.3