On Sun, Mar 26, 2017 at 6:04 PM Joshua Schaeffer <jschaeffer0...@gmail.com> wrote:
> > On 03/26/2017 08:30 AM, Cindy-Sue Causey wrote: > > > In the case I'm thinking, it's about manually adding multiple lines to > a file that I'm not completely remembering just now. Gut is saying > it's /etc/network/interfaces. Mine's almost empty so I don't have an > example to confirm that. > > Typically user's put a second gateway option in the /etc/network/interface > file (which you talk about in the next paragraph). This usually results in > not understanding what the gateway does. > > What I encountered wasn't about declaring different values for > gateway, either. For whatever reasons due to innate [functionality], > it becomes a fail even if you declare the same gateway value for that > line within each new, separate block of declarations. Success is found > by declaring it once then omitting that line within any other new > blocks added over time. > > While I've never put duplicate gateway information in > /etc/network/interfaces I, at one point when learning about networking and > setting it up in Debian, had put a gateway for each subnet in the > interfaces file (which is incorrect and resulted in an error). A gateway, > often called a "gateway of last resort" tells the system how to reach > subnets that it is not attached to. That is the point of the gateway; it is > the one place the system can send packets to when it doesn't know where to > go. If you defined two gateways (meaning if this was allowed) you would be > back to square one, the system wouldn't know which gateway to send the > packet to. Defining two gateways could be an incorrect way of saying you > are defining two routes (most likely static routes). > > Between my setup and cognition, I've never had anything stable enough > to test if it matters which block that gateway is declared. I've > wondered if it matters that it be in the first block, or if it just > needs to show up somewhere in that file. I was consciously putting it > in the first block because that seemed to be the *logical* thing to do > k/t having touched on programming 20 years ago at a local tech school. > > I hadn't really thought about this myself. I've always defined the gateway > under the interface that is attached to the subnet where the gateway > resides. A.K.A. if I have two networks: > > auto eth0 > iface inet eth0 static > address 192.168.0.2/24 > > auto eth1 > iface inet eth1 static > address 10.1.10.2/24 > > And my gateway of last resort was on the 192.168.0 subnet then I would > define the gateway under that interface > > auto eth0 > iface inet eth0 static > address 192.168.0.2/24 > gateway 192.168.0.1 > > It never occurred to me to see if it could be put anywhere in the file. My > hunch is it can and I guess I could take the 60 seconds to test it, but > I'll leave that to more adventurous people. > > > Thanks, > Joshua Schaeffer > I had simply done a route add so I reversed it with a route del. -- Regards, Phil
