Bug 61968

Summary: ab fails to connect to localhost (111)
Product: Apache httpd-2 Reporter: Yuri Kanivetsky <yuri.kanivetsky>
Component: CoreAssignee: Apache HTTPD Bugs Mailing List <bugs>
Status: NEW ---    
Severity: normal    
Priority: P2    
Version: 2.4.29   
Target Milestone: ---   
Hardware: PC   
OS: Linux   

Description Yuri Kanivetsky 2018-01-05 15:33:28 UTC
The following command fails:

$ ab -n 1 localhost:8000/
Benchmarking localhost (be patient)...apr_socket_recv: Connection refused (111)

But this one succeeds:

$ ab -n 1

In /etc/hosts I have:   localhost.localdomain   localhost
::1     localhost.localdomain   localhost

The issue here is caused by ab taking the first result returned by apr_sockaddr_info_get:


But apr_sockaddr_info_get returns a list. If it were to try the second sockaddr structure, it would connect. This way it works:

    rv = apr_sockaddr_info_get(&sa, REMOTE_HOST, APR_UNSPEC, REMOTE_PORT, 0, mp);
    if (rv != APR_SUCCESS) {
        return rv;
    for ( ; sa; sa = sa->next) {
        rv = apr_socket_create(&s, sa->family, SOCK_STREAM, APR_PROTO_TCP, mp);
        if (rv != APR_SUCCESS) {
            return rv;

        apr_socket_opt_set(s, APR_SO_NONBLOCK, 1);
        apr_socket_timeout_set(s, SOCK_TIMEOUT);

        rv = apr_socket_connect(s, sa);
        if (rv == ECONNREFUSED) {
        } else if (rv == APR_SUCCESS) {
        } else {
            return rv;

    apr_socket_opt_set(s, APR_SO_NONBLOCK, 0);
    apr_socket_timeout_set(s, SOCK_TIMEOUT);

Other tools (like, curl, wget, w3m) deal with it just fine.

P.S. A couple of links just in case

Comment 1 Yuri Kanivetsky 2018-01-05 15:36:28 UTC
apr_socket_{opt_set,timeout_set} are taken from this tutorial: http://dev.ariel-networks.com/apr/apr-tutorial/html/apr-tutorial-13.html