autofs-5.1.1 - add configuration option to use fqdn in mounts

From: Ian Kent <raven@themaw.net>

When a server name returns multiple IP addresses autofs uses the IP

address when performing the mount to ensure that the the host proximity

order is respected, and that servers that aren't responding aren't

tried.

But sometimes people need to use the server name for the mount so

add a configuration option to enable that.

Signed-off-by: Ian Kent <raven@themaw.net>

---

 CHANGELOG                      |    1 +

 include/defaults.h             |    3 +++

 lib/defaults.c                 |   18 ++++++++++++++++++

 man/autofs.conf.5.in           |   18 ++++++++++++++++++

 modules/mount_nfs.c            |    3 ++-

 modules/replicated.c           |    6 ++++++

 redhat/autofs.conf.default.in  |    8 ++++++++

 samples/autofs.conf.default.in |    8 ++++++++

 8 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG b/CHANGELOG

index 2b8d224..2c516e4 100644

--- a/CHANGELOG

+++ b/CHANGELOG

@@ -19,6 +19,7 @@

 - fix update_hosts_mounts() return.

 - change lookup to use reinit instead of reopen.

 - update map_hash_table_size description.

+- add configuration option to use fqdn in mounts.

 21/04/2015 autofs-5.1.1

 =======================

diff --git a/include/defaults.h b/include/defaults.h

index 4f32e12..3788078 100644

--- a/include/defaults.h

+++ b/include/defaults.h

@@ -47,6 +47,8 @@

 #define DEFAULT_MAP_HASH_TABLE_SIZE	"1024"

+#define DEFAULT_USE_HOSTNAME_FOR_MOUNTS	"0"

+

 /* Config entry flags */

 #define CONF_NONE			0x00000000

 #define CONF_ENV			0x00000001

@@ -162,6 +164,7 @@ unsigned int defaults_get_mount_wait(void);

 unsigned int defaults_get_umount_wait(void);

 const char *defaults_get_auth_conf_file(void);

 unsigned int defaults_get_map_hash_table_size(void);

+unsigned int defaults_use_hostname_for_mounts(void);

 unsigned int conf_amd_mount_section_exists(const char *);

 char *conf_amd_get_arch(void);

diff --git a/lib/defaults.c b/lib/defaults.c

index 74fafc5..7159536 100644

--- a/lib/defaults.c

+++ b/lib/defaults.c

@@ -73,6 +73,8 @@

 #define NAME_MAP_HASH_TABLE_SIZE	"map_hash_table_size"

+#define NAME_USE_HOSTNAME_FOR_MOUNTS	"use_hostname_for_mounts"

+

 #define NAME_AMD_ARCH				"arch"

 #define NAME_AMD_AUTO_ATTRCACHE			"auto_attrcache"

 #define NAME_AMD_AUTO_DIR			"auto_dir"

@@ -335,6 +337,11 @@ static int conf_load_autofs_defaults(void)

 	if (ret == CFG_FAIL)

 		goto error;

+	ret = conf_update(sec, NAME_USE_HOSTNAME_FOR_MOUNTS,

+			  DEFAULT_USE_HOSTNAME_FOR_MOUNTS, CONF_ENV);

+	if (ret == CFG_FAIL)

+		goto error;

+

 	/* LDAP_URI and SEARCH_BASE can occur multiple times */

 	while ((co = conf_lookup(sec, NAME_LDAP_URI)))

 		conf_delete(co->section, co->name);

@@ -1701,6 +1708,17 @@ unsigned int defaults_get_map_hash_table_size(void)

 	return (unsigned int) size;

 }

+unsigned int defaults_use_hostname_for_mounts(void)

+{

+	int res;

+

+	res = conf_get_yesno(autofs_gbl_sec, NAME_USE_HOSTNAME_FOR_MOUNTS);

+	if (res < 0)

+		res = atoi(DEFAULT_USE_HOSTNAME_FOR_MOUNTS);

+

+	return res;

+}

+

 unsigned int conf_amd_mount_section_exists(const char *section)

 {

 	return conf_section_exists(section);

diff --git a/man/autofs.conf.5.in b/man/autofs.conf.5.in

index 4434eb8..6eb5d02 100644

--- a/man/autofs.conf.5.in

+++ b/man/autofs.conf.5.in

@@ -111,6 +111,24 @@ entries, in this case, is usually much less than the number of entries

 in the map. In this last case it would be unusual for the map entry

 cache to grow large enough to warrant increasing the default before

 an event that cleans stale entries, a map re-read for example.

+.TP

+.B use_hostname_for_mounts

+.br

+NFS mounts where the host name resolves to more than one IP address

+are probed for availability and to establish the order in which mounts

+to them should be tried. To ensure that mount attempts are made only

+to hosts that are responding and are tried in the order of hosts with

+the quickest response the IP address of the host needs to be used for

+the mount.

+

+If it is necessary to use the hostname given in the map entry for the

+mount regardless, then set this option to "yes".

+

+Be aware that if this is done there is no defense against the host

+name resolving to one that isn't responding and while the number

+of attempts at a successful mount will correspond to the number of

+addresses the host name resolves to the order will also not correspond

+to fastest responding hosts.

 .SS LDAP Configuration

 .P

 Configuration settings available are:

diff --git a/modules/mount_nfs.c b/modules/mount_nfs.c

index 15e1043..aa786f3 100644

--- a/modules/mount_nfs.c

+++ b/modules/mount_nfs.c

@@ -316,7 +316,8 @@ dont_probe:

 		/* Not a local host - do an NFS mount */

-		if (this->rr && this->addr) {

+		if (this->rr && this->addr &&

+		    !defaults_use_hostname_for_mounts()) {

 			socklen_t len = INET6_ADDRSTRLEN;

 			char n_buf[len + 1];

 			const char *n_addr;

diff --git a/modules/replicated.c b/modules/replicated.c

index 32860d5..8437f5f 100644

--- a/modules/replicated.c

+++ b/modules/replicated.c

@@ -667,6 +667,12 @@ int prune_host_list(unsigned logopt, struct host **list,

 	if (!*list)

 		return 0;

+	/* If we're using the host name then there's no point probing

+	 * avialability and respose time.

+	 */

+	if (defaults_use_hostname_for_mounts())

+		return 1;

+

 	/* Use closest hosts to choose NFS version */

 	first = *list;

diff --git a/redhat/autofs.conf.default.in b/redhat/autofs.conf.default.in

index da0882f..b751043 100644

--- a/redhat/autofs.conf.default.in

+++ b/redhat/autofs.conf.default.in

@@ -142,6 +142,14 @@ mount_nfs_default_protocol = 4

 #

 #map_hash_table_size = 1024

 #

+# use_hostname_for_mounts - nfs mounts where the host name resolves

+# 			 to more than one IP address normally need

+# 			 to use the IP address to esure a mount to

+# 			 a host that isn't responding isn't done.

+# 			 If that behaviour is not wanted then set

+#			 ths to "yes", default is "no".

+#

+#use_hostname_for_mounts = "no"

 #

 # Otions for the amd parser within autofs.

 #

diff --git a/samples/autofs.conf.default.in b/samples/autofs.conf.default.in

index 80abb43..4b48c63 100644

--- a/samples/autofs.conf.default.in

+++ b/samples/autofs.conf.default.in

@@ -141,6 +141,14 @@ browse_mode = no

 #

 #map_hash_table_size = 1024

 #

+# use_hostname_for_mounts - nfs mounts where the host name resolves

+# 			to more than one IP address normally need

+# 			to use the IP address to esure a mount to

+# 			a host that isn't responding isn't done.

+# 			If that behaviour is not wanted then set

+#			ths to "yes", default is "no".

+#

+#use_hostname_for_mounts = "no"

 #

 # Otions for the amd parser within autofs.

 #