diff options
Diffstat (limited to 'sys/netinet/libalias/libalias.3')
| -rw-r--r-- | sys/netinet/libalias/libalias.3 | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/sys/netinet/libalias/libalias.3 b/sys/netinet/libalias/libalias.3 index 42840af..36788d5 100644 --- a/sys/netinet/libalias/libalias.3 +++ b/sys/netinet/libalias/libalias.3 @@ -376,6 +376,14 @@ is called to change the address after .Fn PacketAliasRedirectPort is called, a zero reference will track this change. .Pp +If the link is further set up to operate for a load sharing, then +.Fa local_addr +and +.Fa local_port +are ignored, and are selected dynamically from the server pool, as described in +.Fn PacketAliasAddServer +below. +.Pp If .Fa remote_addr is zero, this indicates to redirect packets from any remote address. @@ -434,6 +442,12 @@ is called to change the address after .Fn PacketAliasRedirectAddr is called, a zero reference will track this change. .Pp +If the link is further set up to operate for a load sharing, then +.Fa local_addr +is ignored, and is selected dynamically from the server pool, as described in +.Fn PacketAliasAddServer +below. +.Pp If subsequent calls to .Fn PacketAliasRedirectAddr use the same aliasing address, all new incoming traffic to this aliasing @@ -471,6 +485,52 @@ If is returned, then the function call did not complete successfully. .Ed .Pp +.Ft int +.Fo PacketAliasAddServer +.Fa "struct alias_link *link" +.Fa "struct in_addr addr" +.Fa "u_short port" +.Fc +.Bd -ragged -offset indent +This function sets the +.Fa link +up for Load Sharing using IP Network Address Translation (RFC 2391, LSNAT). +LSNAT operates as follows. +A client attempts to access a server by using the server virtual address. +The LSNAT router transparently redirects the request to one of the hosts +in server pool, selected using a real-time load sharing algorithm. +Multiple sessions may be initiated from the same client, and each session +could be directed to a different host based on load balance across server +pool hosts at the time. +If load share is desired for just a few specific services, the configuration +on LSNAT could be defined to restrict load share for just the services +desired. +.Pp +Currently, only the simplest selection algorithm is implemented, where a +host is selected on a round-robin basis only, without regard to load on +the host. +.Pp +First, the +.Fa link +is created by either +.Fn PacketAliasRedirectPort +or +.Fn PacketAliasRedirectAddr . +Then, +.Fn PacketAliasAddServer +is called multiple times to add entries to the +.Fa link Ns 's +server pool. +.Pp +For links created with +.Fn PacketAliasRedirectAddr , +the +.Fa port +argument is ignored and could have any value, e.g. htons(~0). +.Pp +This function returns 0 on success, -1 otherwise. +.Ed +.Pp .Ft void .Fn PacketAliasRedirectDelete "struct alias_link *link" .Bd -ragged -offset indent |
