GaleLB: multi-node L4 load balancer

Supports:

• L3-Based Forwarding (Stateless IP Routing in XDP)
• L4-Based Forwarding (Stateful NAT with Connection Tracking in XDP + TC)]

Requirements

Architecture

Configuration

Load balancer configuration:

[local]
# port opened to listen for incoming connections from nodes
node_port = 7070
# port opened to listen for incoming connections from clients
clients_port = 8080
# interface used to retrieve and re-route network packets from clients 
net_interface_clients = "eno1"

[node_health]
# number of continuous health checks that must be passed before being eligible for routing destination
checks_before_routing = 3
# duration of deadline between health checks, after this period, nodes will be removed from the routing ring
checks_timeout = "5s"

# number of times nodes can fail to send health checks before they are blacklisted
# ex: the node will be added and removed 5 times to the routing table before they will start to be completly ignored.
# use -1 if want to disable this option
black_list_after_fails = 5

# duration of the ban
black_list_expiry = "5m"

[load_balancer_quorum]
# enforce_single_configuration is used to enforce that all load balancers must have the same configuration regarding
# nodes (ex: node health timeout). If this option is set to true, the load balancers will have to contain the same
# parameters in order to reach consensus. If a load balancer tries to connect with a different configuration, it will
# be ignored
enforce_single_configuration = false

#addresses = [
#    { ip = "192.168.1.1", port = 7070 },
#    { ip = "192.168.1.2", port = 8080 },
#    { ip = "192.168.1.3", port = 9090 }
#]

Node configuration:

[load_balancer]
addresses = [
    { ip = "192.168.1.1", port = 7070 },
    { ip = "192.168.1.2", port = 8080 },
    { ip = "192.168.1.3", port = 9090 }
]

Example

To run the Gale load balancer, make sure you have the necessary permissions. Elevated privileges are required to adjust the rlimit and load the XDP module. You can run the load balancer with the following command:

$ sudo ./bin/gale-lb --config cmd/lb.toml

Dependencies

Install dependencies for building eBPF programs:

$ sudo apt-get install clang llvm libbpf-dev gcc make
$ sudo apt install linux-headers-$(uname -r)

Install linter:

$ go install github.com/golangci/golangci-lint/cmd/[email protected]

Install protobuf and protoc:

$ go get google.golang.org/protobuf/cmd/protoc-gen-go
$ go install google.golang.org/grpc/cmd/protoc-gen-go-grpc