Manual login isn't really going to cut it, because I may not be around when things go pear shaped, or I may be asleep. The only scenario that would work for a manual login is if a screwy power supply takes down the power line Ethernet, because I'll know about that. And if I'm going to manually login to fix things, it's even easier to do the obvious and swap over the cat 5 cable at one of the switches to achieve that result. :)
On Sunday, April 21, 2013, Russell Coker wrote:
Firstly I'm moving this to luv-main because it's about serious Linux
networking issues.
On Sun, 21 Apr 2013, Tony Langdon <vk3jed@gmail.com> wrote:
> About to rebuild the network here after moving house. One issue I'm
> contemplating is performance and redundancy. One part of the network
> can't (easily) be reached by Cat 5/6, running cables t that part of the
> house would be too messy at best. I have two ways I can bridge this gap
> - Powerline Ethernet adapters, which have worked extremely well in the
> past, or WiFi, using an access point in client bridge mode.
>
> Now the powerline adapters do work extremely well, with a rated speed of
> 85 Mbps. I've never had an issue, except for the switchmode supply of
> one laptop, which trashed the link (took a bit of detective work that
> one!). The biggest weakness of these devices is that they can't be
> battery backed up. If the mains goes down, so do they.
http://etbe.coker.com.au/2010/08/04/clusters-dont-work/
I wrote the above blog post about my experience with clusters. Some of this
applies to failover of links.
One significant difference between a home network and a serious server network
is that most of the functions of your home network don't matter much when you
are asleep or away. Therefore a redundancy which involves you logging in as
root and running a route command will work a lot better on a home network. Of
course my experience is that having a sysadmin login as root and manually fail
things over is better than any cluster software implementation I've seen, but
that's another issue.
> WiFi can be backed up, especially since a lot of the gear I have will
> happily run off a 12V battery, and some of the systems on the far end
> will be running off a battery backed DC supply. However, performance
> with the WiFi solution isn't as good.
>
> Is there a way I can (easily and cheaply) arrange to run on the
> powerline devices by default and fail over to WiFi, if the power goes down?
How often does power go down anyway?
--
My Main Blog http://etbe.coker.com.au/
My Documents Blog http://doc.coker.com.au/