From 3fa032744e94b1a59ff3e2b38c35ca66a6e24d56 Mon Sep 17 00:00:00 2001 From: Suzanne Goldlust Date: Mon, 7 Jan 2019 15:59:26 -0500 Subject: [PATCH] Update hooks-ha.xml --- doc/guide/hooks-ha.xml | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/doc/guide/hooks-ha.xml b/doc/guide/hooks-ha.xml index f05d6abd34..cb7d6f6ab6 100644 --- a/doc/guide/hooks-ha.xml +++ b/doc/guide/hooks-ha.xml @@ -10,7 +10,7 @@ ha: High Availability This section describes the High Availability hooks library, which can be - loaded on a pair of DHCPv4 or DHCPv6 servers to increase reliability of + loaded on a pair of DHCPv4 or DHCPv6 servers to increase the reliability of the DHCP service in the event of an outage of one of the servers. This library was previously only available to ISC's paid subscribers, but is now part of the open source Kea, available to all users. @@ -31,7 +31,7 @@ significant features are communication between the servers, partner failure detection, and lease synchronization between the servers. However, the DHCPv4 failover standardization process was never completed - at IETF. The DHCPv6 failover standard (RFC 8156) was published, but it + by the IETF. The DHCPv6 failover standard (RFC 8156) was published, but it is complex, difficult to use, has significant operational constraints, and is different than its v4 counterpart. Although it may be useful for some users to use a "standard" failover @@ -55,7 +55,7 @@ The Kea HA hook library supports two configurations, also known as HA modes: load balancing and hot standby. In the load-balancing mode, two servers respond to DHCP requests. The load-balancing function - is implemented as described in RFC3074, with each server responding to + is implemented as described in RFC 3074, with each server responding to half the received DHCP queries. When one of the servers allocates a lease for a client, it notifies the partner server over the control channel (RESTful API), so the partner can save the lease information in its @@ -570,7 +570,7 @@ into account the specifics of the network in which the DHCP servers are operating. Note that the server in question may not respond to some DHCP clients because these clients are not to be serviced - by this server per administrative policy. The server may also + by this server according to administrative policy. The server may also drop malformed queries from clients. Therefore, selecting too low a value for the max-unacked-clients parameter may result in a transition to the partner-down @@ -897,7 +897,7 @@ and/or database synchronization between the active servers, if the exchange of information about the allocated leases is performed using some other mechanism. Kea supports various database types - to be used as storage for leases, including MySQL, Postgres, and Cassandra. + that can be used to store leases, including MySQL, Postgres, and Cassandra. Those databases include built-in solutions for data replication which are often used by Kea administrators to provide redundancy. @@ -979,14 +979,14 @@ Increasing the page size decreases the number of lease queries sent to the partner server, but it causes the partner server to generate larger responses, which lengthens transmission time as well as - memory and CPU utilization on both servers. Decreasing the + increases memory and CPU utilization on both servers. Decreasing the page size helps to decrease resource utilization, but requires more lease queries to be issued to fetch the entire lease database. The default value of the sync-page-limit command controlling the page size is 10000. This means that the entire lease database can be fetched with a single command if the - size of the database is equal to or lower than 10000 lines. + size of the database is equal to or less than 10000 lines. @@ -1059,7 +1059,7 @@ It is important to note that extending this sync-timeout value may sometimes be insufficient to prevent issues with timeouts during - lease-database synchronization. The control commands travel via + lease-database synchronization. The control commands travel via the Control Agent, which also monitors incoming (with a synchronizing server) and outgoing (with a DHCP server) connections for timeouts. The DHCP server also monitors the connection from the Control @@ -1347,7 +1347,7 @@ - When the server receives this command, it first disables the + When the server receives this command it first disables the DHCP service of the server from which it will be fetching leases, by sending the dhcp-disable command to that server. The max-period parameter specifies the maximum -- 2.47.2