From: Grant Slater <git@firefishy.com>
Date: Sat, 22 Feb 2020 22:13:47 +0000 (+0000)
Subject: Force Enable TCP MTU probing @ UCL
X-Git-Url: https://git.openstreetmap.org./chef.git/commitdiff_plain/b1ced9fbdbe88a53f3b96236ea82cb85f85262cc

Force Enable TCP MTU probing @ UCL
---

diff --git a/roles/ucl.rb b/roles/ucl.rb
index 27064ea23..eb3dfd1cd 100644
--- a/roles/ucl.rb
+++ b/roles/ucl.rb
@@ -19,6 +19,15 @@ default_attributes(
         }
       }
     }
+  },
+  :sysctl => {
+    :blackhole => {
+      :comment => "Force TCP level MTU probing because of known ICMP blackhole at UCL",
+      :parameters => {
+        "net.ipv4.tcp_mtu_probing" => "2",
+        "net.ipv4.tcp_base_mss" => "1024"
+      }
+    }
   }
 )