NimbostratusWebsocket failover by LB_FAILED
We have an application which uses websockets to connect to the server from the client side.
Now in the iRule we have mentioned in HTTP_REQUEST event that for websocket the HTTP::disable will be called and all the connection will be listen on tcp sockets opened from the client side.
If one client is connected to the server 1 with this method, now if that server went down now it will retry to another server by LB_FAILED event. So as in the HTTP_REQUEST we have disabled the HTTP requests the F5 LTM is not retrying it to the new node.
Following is the iRule :
In the iRule you can see we are disabling the HTTP when we receive /api/channel/websocket uri in header. If we don't disable the HTTP the websocket doest not gets created. Now if the one server goes down the request will trigger LB_FAILED event with HTTP as disabled. So the request doest not get to the new node and it fails. Can we have mechanism we can save HTTP headers over the tcp websockets by iRule.
when HTTP_REQUEST {
set uri [HTTP::uri]
if { [HTTP::header exists "objectId"] or [string tolower $uri] contains "/api/channel/websocket" }
{
set orgid [crc32 [HTTP::header objectId]]
set key [expr $orgid % [llength [members -list default_pool]]]
set default_member [lsort [members -list default_pool]]
set channel_member [lsort [members -list channel-pool]]
set gateway_member [lsort [members -list gateway-pool]]
set space_member [lsort [members -list space-pool]]
log "[HTTP::uri]"
if { [string tolower $uri] contains "/api/channel/websocket" }
{
HTTP::disable
log "[lindex [lindex $channel_member $key] 0] [lindex [lindex $channel_member $key] 1]"
pool channel-pool member [lindex [lindex $channel_member $key] 0] [lindex [lindex $channel_member $key] 1]
} else {
switch -glob [string tolower $uri] {
"/api/channel*" { pool channel-pool member [lindex [lindex $channel_member $key] 0] [lindex [lindex $channel_member $key] 1] }
"/api/space*" {pool space-pool member [lindex [lindex $space_member $key] 0] [lindex [lindex $space_member $key] 1] }
"/api/gateway*" { pool gateway-pool member [lindex [lindex $gateway_member $key] 0] [lindex [lindex $gateway_member $key] 1] }
default { pool default_pool member [lindex [lindex $default_member $key] 0] [lindex [lindex $default_member $key] 1] }
}
}
} elseif { [string tolower $uri] contains "/api/gateway/sendmessage" }
{
switch [string tolower $uri] {
"/api/gateway/sendmessage" { pool sendmessage-pool }
}
}
}
when LB_FAILED {
set uri [HTTP::uri]
set orgid_new [crc32 [HTTP::header objectId]]
set newkey [expr $orgid_new % [active_members default_pool]]
set default_member_new [lsort [active_members -list default_pool]]
set channel_member_new [lsort [active_members -list channel-pool]]
set gateway_member_new [lsort [active_members -list gateway-pool]]
set space_member_new [lsort [active_members -list space-pool]]
if { [string tolower $uri] contains "/api/channel/websocket" }
{
log "[HTTP::uri]"
HTTP::disable
log "[lindex [lindex $channel_member_new $key] 0] [lindex [lindex $channel_member_new $key] 1]"
LB::reselect pool channel-pool member [lindex [lindex $channel_member_new $key] 0] [lindex [lindex $channel_member_new $key] 1]
} else {
switch -glob [string tolower $uri] {
"/api/channel*" {
log "[lindex [lindex $channel_member_new $key] 0] [lindex [lindex $channel_member_new $key] 1]"
LB::reselect pool channel-pool member [lindex [lindex $channel_member_new $key] 0] [lindex [lindex $channel_member $key] 1]
}
"/api/space*" {
log "[lindex [lindex $space_member_new $key] 0] [lindex [lindex $space_member_new $key] 1]"
LB::reselect pool space-pool member [lindex [lindex $space_member_new $key] 0] [lindex [lindex $space_member_new $key] 1]
}
"/api/gateway*" {
log "[lindex [lindex $gateway_member_new $key] 0] [lindex [lindex $gateway_member_new $key] 1]"
LB::reselect pool gateway-pool member [lindex [lindex $gateway_member_new $key] 0] [lindex [lindex $gateway_member_new $key] 1]
}
default {
log "[lindex [lindex $default_member_new $key] 0] [lindex [lindex $default_member_new $key] 1]"
LB::reselect pool default_pool member [lindex [lindex $default_member_new $key] 0] [lindex [lindex $default_member_new $key] 1]
}
}
}
}
If anybody can provide any help on this?
Thanks.
