systemd: increase default timeout of NetworkManager-wait-online

We encountered the following situation:

• nm-online (NetworkManager-wait-online.service) is started
• NetworkManager tries to configure network
• the first try of using dhclient fails with timeout for some reasons
• the second try of running dhclient completes successfully (NMs tries himself) We get a working network, but it takes more that 30 seconds.

NetworkManager-wait-online.service fails, it may be a false negative to checkers of network being online. It will also be a false positive signal to start mounting network (CIFS, NFS etc.) shares, for example, because they depend from network-online.target and network-online.target will become reached right after NetworkManager-wait-online.service fails.

So, it makes sense to increase default timeout from 30 to 60 seconds.

@thaller wrote in #237 (closed) that there may be cases where, for example, incorrectly set up bridges or just network may lead to delays when booting the system.

Yes, but:

• if there is no possibility to start trying to connect the network, e.g. if all network interfaces, managed by NetworkManager, are DOWN, NM will not try to connect network and "nm-online -s" will exit with 0 without waiting (so, this will not prolong start up of workstations or servers when ethernet cable is just not plugged in)
• an additional potential 30 seconds delay seems to be less harmful then a false positive to start mounting network shares or doing abything else too eraly, when an additional wait for a few seconds would have prevented those things from failing.

All things considered, it seems reasonable to increase this timeout from 30 seconds to 1 munite (60 seconds).

Signed-off-by: Mikhail Novosyolov m.novosyolov@rosalinux.ru