diff --git a/lib/httpx/connection.rb b/lib/httpx/connection.rb
index 7c4fb102..bc2b0c3e 100644
--- a/lib/httpx/connection.rb
+++ b/lib/httpx/connection.rb
@@ -522,14 +522,15 @@ module HTTPX
            Errno::ENETUNREACH,
            Errno::EPIPE,
            Errno::ENOENT,
-           SocketError => e
+           SocketError,
+           IOError => e
       # connect errors, exit gracefully
       error = ConnectionError.new(e.message)
       error.set_backtrace(e.backtrace)
       connecting? && callbacks_for?(:connect_error) ? emit(:connect_error, error) : handle_error(error)
       @state = :closed
       emit(:close)
-    rescue TLSError => e
+    rescue TLSError, HTTP2Next::Error::ProtocolError, HTTP2Next::Error::HandshakeError => e
       # connect errors, exit gracefully
       handle_error(e)
       connecting? && callbacks_for?(:connect_error) ? emit(:connect_error, e) : handle_error(e)
diff --git a/lib/httpx/io/tcp.rb b/lib/httpx/io/tcp.rb
index ea990f6d..a16ad73a 100644
--- a/lib/httpx/io/tcp.rb
+++ b/lib/httpx/io/tcp.rb
@@ -78,7 +78,8 @@ module HTTPX
     rescue Errno::ECONNREFUSED,
            Errno::EADDRNOTAVAIL,
            Errno::EHOSTUNREACH,
-           SocketError => e
+           SocketError,
+           IOError => e
       raise e if @ip_index <= 0
 
       log { "failed connecting to #{@ip} (#{e.message}), trying next..." }