On 06/08/2015 02:43 PM, Laine Stump wrote:
However, if I changed the destination address from "anywhere" to the IP of the host machine, the problem resolved. So I change the script to as follows. (Changes are highlighted. For some reason the original script didn't work using /bin/sh, but it did with /bin/bash, so I changed that too).
I don't know for sure, but my guess is that this line:
length=$(( ${#Host_port[@]} - 1 ))
Correct - that line is a bashism, and is not portable when /bin/sh is dash.
which was added by vgerris in order to support forwarding of multiple ports, could be what's causing the incompatibility (that wasn't in the original, simpler version of the script, written by me.)
*#!/bin/bash* # used some from advanced script to have multiple ports: use an equal number of guest and host ports
Guest_name=xxxxxxx Guest_ipaddr=xxx.xxx.xxx.xx *Host_ipaddr=xxx.xxx.xxx.xx* Host_port=( '80' '443' ) Guest_port=( '80' '443' )
In fact, these two lines are also bashisms. All the more reason to require bash.
length=$(( ${#Host_port[@]} - 1 )) if [ "${1}" = "${Guest_name}" ]; then if [ "${2}" = "stopped" -o "${2}" = "reconnect" ]; then
test ... -o ... (also spelled [ ... -o ... ]) is not portable, even on bash. There are some expressions that are completely ambiguous on how to be parsed, when -o is in the mix. It is better to spell it: [ ... ] || [ ... ] (that is, use the shell's || instead of test's -o to do the conjunction).
for i in `seq 0 $length`; do
seq is not portable outside of GNU/Linux systems.
Lastly, I should note that I am using Ubuntu 14.04, both for the host and guest.
Yep, that's a system that uses dash for /bin/sh.
I'm also curious as to why this is considered a hack method. It states in the wiki that "This method is a hack", but it doesn't express why.
I consider it a hack because:
1) It requires the IP address of the guest to be known before the guest is started, so either you need to guess the guest's IP (if the guest is getting its IP address via dhcp) or configured the guest IP address in multiple places.
Although recent work has been made to get libvirt to add an API that queries the guest for its IP address, once the guest is running. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org