Dmitrii Stepanov
e35ad63f2d
The use of network interfaces does not cover cases where it is necessary to use network interfaces to access different subnets. Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>
56 lines
1.4 KiB
Markdown
56 lines
1.4 KiB
Markdown
# 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 (
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"context"
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"net"
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"net/netip"
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"git.frostfs.info/TrueCloudLab/multinet"
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)
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import
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d, err := multinet.NewDialer(Config{
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Subnets: []Subnet{
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{
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Prefix: netip.MustParsePrefix("10.11.70.0/23"),
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SourceIPs: []netip.Addr{
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netip.MustParseAddr("10.11.70.42"),
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netip.MustParseAddr("10.11.71.42"),
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},
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},
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{
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Prefix: netip.MustParsePrefix("192.168.123.0/24"),
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SourceIPs: []netip.Addr{
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netip.MustParseAddr("192.168.123.42"),
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netip.MustParseAddr("192.168.123.142"),
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},
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},
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},
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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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