npm install sticky-session
var cluster = ; // Only required if you want the worker idvar sticky = ;var server =;if !sticky// Master codeserver;else// Worker code
Socket.io is doing multiple requests to perform handshake and establish
connection with a client. With a
cluster those requests may arrive to
different workers, which will break handshake protocol.
Sticky-sessions module is balancing requests using their IP address. Thus client will always connect to same worker server, and socket.io will work as expected, but on multiple processes!
node to be at least
0.12.0 because it relies on
A deeper, step-by-step explanation on how this works can be found in
This software is licensed under the MIT License.
Copyright Fedor Indutny, 2015.
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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