haproxy Settings for Blockscout.com

Blockscout.com uses haproxy for all BlockScout hosted and external instances.

If you would like to add your instance to Blockscout.com, make the required changes and submit a PR to https://github.com/blockscout/haproxy-config

Instructions

Blockscout uses two-part path names for network urls: the first part (org) designates the organization/type of the network, the second part (netname) names the network.

For example:

• Eth mainnet: https://blockscout.com/eth/mainnet (org=eth, netname=mainnet)

• Ethereum Classic mainnet: https://blockscout.com/etc/mainnet (org=etc, netname=mainnet)

• Kovan testnet: https://blockscout.com/eth/kovan (org=eth, netname=kovan)

1. Add a new org for your blockscout instance's url

1) Add a new acl under the #Check for network type section in the cfg file.

#Check for network type
...
acl is_myorg path_beg -i /myorg

2) Add a corresponding exception !is_myorg to the #default redirect section

# default redirect
redirect prefix /poa/xdai if !is_websocket !is_poa !is_etc !is_eth !is_lukso !is_rsk !is_myorg !is_cookie

3) add !is_myorg to every line in the #redirect for networks section

#redirect for networks
redirect prefix /poa/core if !is_websocket !is_poa !is_etc !is_eth !is_lukso !is_rsk !is_myorg is_cookie_core
redirect prefix /poa/sokol if !is_websocket !is_poa !is_etc !is_eth !is_lukso !is_rsk !is_myorg is_cookie_sokol
# do this for every line
...

2. Add a new acl with your netname

In the #Check for network name section add a new acl with your netname similar to existing ones

#Check for network name
...
acl is_mynet path_beg -i /myorg/mynet

3) Set the cookie and name of rpc/websockets servers

#Check for cookies
...
acl is_cookie_mynet hdr_sub(cookie) network=mynet

#Default backends
...
use_backend mynet if is_mynet

#WebSocket backends
...
use_backend mynet_ws if is_cookie_mynet is_websocket

4. Add new backend sections to the end of the file

Add new backend_mynet and backend_mynet_ws sections to the end of the file and provide dns names of your BlockScout instances.

For example:

backend mynet
    #Proxy mode
    mode http

    #Backend queries should not have network prefix, so we delete it
    acl is_mynet path_beg /myorg/mynet
    reqirep ^([^\ ].*)myorg/mynet[/]?(.*) \1\2 if is_mynet

    #Setting headers to mask our query
    http-request set-header X-Forwarded-Host %[req.hdr(Host)]
    http-request set-header X-Client-IP %[src]
    http-request set-header Host my-blockscout-instance.com

    #Specifying cookie to insert
    cookie network insert

    #Server list. Format:
    #server <name> <address>:<port> cookie <network_name> check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none
    server mynet_server my-blockscout-instance.com:443 cookie mynet check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none

backend mynet_ws
    #Check if WebSocket request is correct
    acl hdr_websocket_key      hdr_cnt(Sec-WebSocket-Key)      eq 1
    acl hdr_websocket_version  hdr_cnt(Sec-WebSocket-Version)  eq 1
    http-request deny if ! hdr_websocket_key ! hdr_websocket_version

    #WebSockets should be forwarded, not http proxied
    option forwardfor

    #Setting headers to mask our query
    http-request set-header Host my-blockscout-instance.com
    http-request set-header Origin https://my-blockscout-instance.com

    #Specifying cookie to insert
    cookie network insert

    #Server list. Format:
    #server <name> <address>:<port> cookie <network_name> check inter 60000 fastinter 1000 fall 3 rise 3 check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none maxconn 30000
    server mynet_server my-blockscout-instance.com:443 cookie mynet check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none maxconn 30000

Change the following parameters to match your specific case

• backend mynet:

  • acl is_...

  • reqirep ...

  • http-request set-header Host ...

  • server mynet_server... - don't forget to specify port 443 here

• backend mynet_ws:

  • http-request set-header Host...

  • http-request set-header Origin ... don't forget https here

  • server mynet_server... - don't forget port 443 here

Submit a PR to the configuration repo at https://github.com/blockscout/haproxy-config