- Using localhost was making the feature test too slow, due to use IPv6 by default in systems that has IPv6 enabled but not properly configured. For example, strace shows several attempts to send data to a socket, being droped when timed out: sendto(4, "W\34\326\267\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\4\0\0\0\3\0\0\0\0\0\0\0\0"..., 84, 0, {sa_family=AF_INET6, sin6_port=htons(111), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 84 poll([{fd=4, events=POLLIN}], 1, 15000) = 0 (Timeout) sendto(4, "W\34\326\267\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\4\0\0\0\3\0\0\0\0\0\0\0\0"..., 84, 0, {sa_family=AF_INET6, sin6_port=htons(111), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 84 poll([{fd=4, events=POLLIN}], 1, 15000) = 0 (Timeout) sendto(4, "W\34\326\267\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\4\0\0\0\3\0\0\0\0\0\0\0\0"..., 84, 0, {sa_family=AF_INET6, sin6_port=htons(111), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 84 poll([{fd=4, events=POLLIN}], 1, 15000) = 0 (Timeout) sendto(4, "W\34\326\267\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\4\0\0\0\3\0\0\0\0\0\0\0\0"..., 84, 0, {sa_family=AF_INET6, sin6_port=htons(111), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 84 poll([{fd=4, events=POLLIN}], 1, 15000) = 0 (Timeout) Both cases are similar: * showmount --no-headers --exports localhost * showmount --no-headers --exports ::1 So, passing 127.0.0.1 we are explicitly requiring a IPv4 connection and that will speed up the feature test *as well as* return the correct result, not a simply timeout: sendto(4, "W\37\256\365\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\2\0\0\0\3\0\0\0\0\0\0\0\0"..., 56, 0, {sa_family=AF_INET, sin_port=htons(111), sin_addr=inet_addr("127.0.0.1")}, 16) = 56 poll([{fd=4, events=POLLIN}], 1, 15000) = 1 ([{fd=4, revents=POLLERR}]) recvmsg(4, {msg_name(16)={sa_family=AF_INET, sin_port=htons(111), sin_addr=inet_addr("127.0.0.1")}, msg_iov(1)=[{"W\37\256\365\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\2\0\0\0\3\0\0\0\0\0\0\0\0"..., 56}], msg_controllen=48, [{cmsg_len=48, cmsg_level=SOL_IP, cmsg_type=IP_RECVERR, {ee_errno=111, ee_origin=2, ee_type=3, ee_code=3, ee_info=0, ee_data=0, offender={sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("127.0.0.1")}}}], msg_flags=MSG_ERRQUEUE}, MSG_ERRQUEUE) = 56 Signed-off-by: Jose Ricardo Ziviani <joserz(a)linux.vnet.ibm.com&gt; --- model/featuretests.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/model/featuretests.py b/model/featuretests.py index 23e7eeb..2b680c3 100644 --- a/model/featuretests.py +++ b/model/featuretests.py @@ -148,7 +148,7 @@ class FeatureTests(object): @staticmethod def libvirt_support_nfs_probe(conn): def _get_xml(): - obj = E.source(E.host(name='localhost'), E.format(type='nfs')) + obj = E.source(E.host(name='127.0.0.1'), E.format(type='nfs')) xml = ET.tostring(obj) return xml try: -- 1.9.1