41 lines
1.1 KiB
Markdown
41 lines
1.1 KiB
Markdown
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# Source-based routing in Golang
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Consider this routing table:
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```
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10.11.70.0/23 dev data0 proto kernel scope link src 10.11.70.42
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10.11.70.0/23 dev data1 proto kernel scope link src 10.11.71.42
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192.168.123.0/24 dev internal0 proto kernel scope link src 192.168.123.42
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192.168.123.0/24 dev internal1 proto kernel scope link src 192.168.123.142
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```
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Simple `net.Dial` to either `10.11.70.42` or `10.11.71.42` will match the first subnet and be routed via data0.
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This problems is usually solved by bonds.
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But sometimes you need to invent a bicycle.
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## Usage
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```golang
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import "git.frostfs.info/TrueCloudLab/multinet"
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d, err := multinet.NewDialer(Config{
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Subnets: []string{"10.11.70.0/23", "192.168.123.0/24"},
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Balancer: multinet.BalancerTypeRoundRobin,
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})
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if err != nil {
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// handle error
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}
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conn, err := d.DialContext(ctx, "tcp", "10.11.70.42")
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if err != nil {
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// handle error
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}
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// do stuff
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```
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### Updating interface state
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`Multidialer` exposes `UpdateInterface()` method for updating state of a single link.
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`NetlinkWatcher` can wrap `Multidialer` type and perform all updates automatically.
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TODO: describe needed capabilities here.
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