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@@ -1,6 +1,6 @@
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-# kolach
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+# Rudder
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-kolach is an overlay network that gives a subnet to each machine for use with
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+Rudder is an overlay network that gives a subnet to each machine for use with
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k8s.
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In k8s every machine in the cluster is assigned a full subnet. The machine A
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@@ -12,13 +12,13 @@ disadvantage is that the only cloud provider that can do this is GCE.
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To emulate the Kubernetes model from GCE on other platforms we need to create
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an overlay network on top of the network that we are given from cloud
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-providers. Kolach uses the Universal TUN/TAP device and creates an overlay network
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+providers. Rudder uses the Universal TUN/TAP device and creates an overlay network
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using UDP to encapsulate IP packets. The subnet allocation is done with the help
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of etcd which maintains the overlay to actual IP mappings.
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## Configuration
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-Kolach reads its configuration from etcd. By default, it will read the configuration
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+Rudder reads its configuration from etcd. By default, it will read the configuration
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from ```/coreos.com/network/config``` (can be overridden via --etcd-prefix).
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The value of the config should be a JSON dictionary with the following keys:
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@@ -36,14 +36,14 @@ the last subnet of Network.
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## Running
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-Once you have pushed configuration JSON to etcd, you can start kolach. If you published your
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-config at the default location, you can start kolach with no arguments. Kolach will acquire a
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+Once you have pushed configuration JSON to etcd, you can start Rudder. If you published your
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+config at the default location, you can start Rudder with no arguments. Rudder will acquire a
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subnet lease, configure its routes based on other leases in the overlay network and start
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routing packets. Additionally it will monitor etcd for new members of the network and adjust
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its routing table accordingly.
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-After kolach has acquired the subnet and configured the TUN device, it will write out an
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-environment variable file (```/run/kolach/subnet.env``` by default) with subnet address and
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+After Rudder has acquired the subnet and configured the TUN device, it will write out an
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+environment variable file (```/run/rudder/subnet.env``` by default) with subnet address and
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MTU that it supports.
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## Key command line options
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@@ -53,19 +53,19 @@ MTU that it supports.
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-etcd-prefix="/coreos.com/network": etcd prefix
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-iface="": interface to use (IP or name) for inter-host communication. Defaults to the interface for the default route on the machine.
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-port=8285: UDP port to use for inter-node communications
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--subnet-file="/run/kolach/subnet.env": filename where env variables (subnet and MTU values) will be written to
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+-subnet-file="/run/rudder/subnet.env": filename where env variables (subnet and MTU values) will be written to
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-v=0: log level for V logs. Set to 1 to see messages related to data path
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```
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## Docker integration
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Docker daemon accepts ```--bip``` argument to configure the subnet of the docker0 bridge. It also accepts ```--mtu``` to set the MTU
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-for docker0 and veth devices that it will be creating. Since kolach writes out the acquired subnet and MTU values into
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+for docker0 and veth devices that it will be creating. Since Rudder writes out the acquired subnet and MTU values into
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a file, the script starting Docker daemon can source in the values and pass them to Docker daemon:
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```bash
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-source /run/kolach/subnet.env
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-docker -d --bip=${KOLACH_SUBNET} --mtu=${KOLACH_MTU}
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+source /run/rudder/subnet.env
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+docker -d --bip=${RUDDER_SUBNET} --mtu=${RUDDER_MTU}
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```
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-Systemd users can use ```EnvironmentFile``` directive in the .service file to pull in ```/run/kolach/subnet.env```
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+Systemd users can use ```EnvironmentFile``` directive in the .service file to pull in ```/run/rudder/subnet.env```
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Eugene Yakubovich