-
Notifications
You must be signed in to change notification settings - Fork 229
Functional Block: CPS
The Control Plane Services (CPS) block has the responsibility of handling all control plane operations for Gatekeeper and Grantor servers. This includes passing any control plane protocol messages to routing daemons running on the host, and accepting routing tables updates from the routing daemons.
Although Gatekeeper servers' main role is only in the data plane, they still need to peer in vantage points and with internal routers of the AS in order to become a node in the ingoing and outgoing network paths.
Instead of adding support for individual control plane protocols like BGP, OSPF, and IS-IS in Gatekeeper, we enable network operators to run control plane daemons on the host. This is a win-win scenario, as Gatekeeper avoids the trouble of supporting these protocols and network operators do not need to learn another tool to manage their routes.
The control plane component accomplishes its goal by steering packets from control plane protocols received on the front and back interfaces and sending them to Kernel NIC Interfaces (KNIs). Routing daemons can receive the control plane packets on KNIs, update and compute new routes, and send them back to Gatekeeper through the KNI as well.
The CPS block is allocated one lcore in Gatekeeper.
All static configuration variables can be configured in lua/cps.lua.
These variables are likely to change from deployment-to-deployment based on the operator's preferences.
kni_kmod_path
The KNI mechanism in DPDK requires the support of a kernel module. The variable defines where in the filesystem the rte_kni.ko kernel module file is found. It should be an absolute (not relative) path.
The log level for the CPS block. Can be set to any one of the following values: RTE_LOG_EMERG, RTE_LOG_ALERT, RTE_LOG_CRIT, RTE_LOG_ERR, RTE_LOG_WARNING, RTE_LOG_NOTICE, RTE_LOG_INFO, RTE_LOG_DEBUG.
Since we typically use RTE_LOG_ERROR as the most severe log condition, we recommend not to set this value below RTE_LOG_ERROR.
It is not crucial to change these variables, and they only need to be changed to fine tune the performance of Gatekeeper. Otherwise, the default values are likely fine.
mailbox_max_entries_exp
The log (base 2) of the maximum size of the CPS mailbox. For example, if the variable is set to 7, then room for 2^7 = 128 entries will be made in the mailbox.
Also used to determine how many entries will actually be available for use in the mailbox, which for efficiency reasons is one less than the maximum size of the mailbox (127 in the example above).
mailbox_mem_cache_size
Number of mailbox entries to keep in the cache for more efficient use of the mailbox. Set to 0 to disable the cache of the memory pool for the mailbox.
mailbox_burst_size
Maximum number of entries to receive in a burst every time the mailbox is checked.
These variables likely only need to be changed under extreme circumstances or for deployment-specific reasons.