new file mode 100644
--- /dev/null
+++ b/upstream_ip_hash.t
@@ -0,0 +1,111 @@
+#!/usr/bin/perl
+
+# (C) Maxim Dounin
+
+# Tests for upstream ip_hash balancer.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+use Socket qw/ CRLF /;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+my $t = Test::Nginx->new()->has(qw/http proxy upstream_ip_hash realip/)
+	->write_file_expand('nginx.conf', <<'EOF')->run();
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    upstream u {
+        ip_hash;
+        server 127.0.0.1:8081;
+        server 127.0.0.1:8082;
+    }
+
+    upstream u2 {
+        ip_hash;
+        server 127.0.0.1:8081;
+        server 127.0.0.1:8082;
+        server 127.0.0.1:8083;
+    }
+
+    server {
+        listen       127.0.0.1:8080;
+        server_name  localhost;
+
+        set_real_ip_from 127.0.0.0/8;
+        add_header X-IP $remote_addr;
+
+        location / {
+            proxy_pass http://u;
+        }
+        location /u2 {
+            proxy_pass http://u2;
+        }
+    }
+
+    server {
+        listen       127.0.0.1:8081;
+        listen       127.0.0.1:8082;
+        listen       127.0.0.1:8083;
+        server_name  localhost;
+
+        location / {
+            add_header X-Port $server_port;
+            return 204;
+        }
+    }
+}
+
+EOF
+
+plan(skip_all => 'no 127.0.0.1 on host')
+	if http_get('/') !~ /X-IP: 127.0.0.1/m;
+
+$t->plan(2);
+
+###############################################################################
+
+is(many('/', 30), '8081: 15, 8082: 15', 'ip_hash');
+is(many('/u2', 30), '8081: 10, 8082: 10, 8083: 10', 'ip_hash 3 peers');
+
+###############################################################################
+
+sub many {
+	my ($uri, $count) = @_;
+	my %ports;
+
+	for my $i (1 .. $count) {
+		my $req = "GET $uri HTTP/1.0" . CRLF
+			. "X-Real-IP: 127.0.$i.2" . CRLF . CRLF;
+
+		if (http($req) =~ /X-Port: (\d+)/) {
+			$ports{$1} = 0 unless defined $ports{$1};
+			$ports{$1}++;
+		}
+	}
+
+	return join ', ', map { $_ . ": " . $ports{$_} } sort keys %ports;
+}
+
+###############################################################################