From: Ian Kent Subject: Re: AutoFS+NFSv4 server down = LOOOOONG timeout. Date: Thu, 27 Aug 2009 16:54:11 +0800 Message-ID: <4A9649B3.7080208@redhat.com> References: <7E189B77-1139-4B16-97E5-4841B41B90C7@oracle.com> <4A82CE18.6020401@redhat.com> <4A82DDB1.1000109@redhat.com> <4A84210F.3020906@redhat.com> <1250555418.16878.7.camel@zeus.themaw.net> <4A92AA43.6070304@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Cc: NFS list , Linux NFSv4 mailing list To: =?ISO-8859-1?Q?Carlos_Andr=E9?= Return-path: In-Reply-To: <4A92AA43.6070304@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nfsv4-bounces@linux-nfs.org Errors-To: nfsv4-bounces@linux-nfs.org List-ID: Ian Kent wrote: > Carlos Andr=E9 wrote: >> Hi Ian, >> >> Thanks for patch and sorry for delay (i'm expecting receive u reply on >> bug track, not here) :) >> >> But, this patch doesnt worked to me like expected... :( >> >> >> Firstly I've changed "#MOUNT_WAIT=3D-1" to "MOUNT_WAIT=3D10" >> and later changed "10" to "2" with same results... >> (always restarting service, of course :) >> >> Then, tried remove "sec=3Dkrb5p", and later removed "nfs4" but i got >> same results again. >> >> Or i'm doing something wrong? >> >> >> [root@KSTATION areas]# automount -V >> >> Linux automount version 5.0.1-0.rc2.131.bz517349.1 >> [...] >> >> [root@KSTATION areas]# time ls -la testdown >> ls: testedown: No such file or directory >> >> real 3m9.006s >> user 0m0.002s >> sys 0m0.000s > = > OK, that isn't behaving the way I expect, I'll have a look. > = >> >> LOGGING: >> ----------------------------------------- >> Aug 24 09:23:51 KSTATION automount[20803]: mount_mount: mount(nfs): >> calling mount -t nfs4 -s -o rw,acl,sec=3Dkrb5p 1.2.3.4:/areas/testdown >> /misc/areas/testdown >> Aug 24 09:27:00 KSTATION automount[20803]: mount(nfs): nfs: mount >> failure 1.2.3.4:/areas/testdown on /misc/areas/testdown >> Aug 24 09:27:00 KSTATION automount[20803]: ioctl_send_fail: token =3D 91 >> Aug 24 09:27:00 KSTATION automount[20803]: failed to mount /misc/areas/t= estdown >> ----------------------------------------- Having a look at this I suspect the reason it doesn't work as expected is the waitpid(2) we do after sending the TERM signal to the mount process (which we have to do) is not returning. This is likely because the mount process isn't giving up in a shorter time as it used to. We could send a KILL signal to the mount process but that does seem to cause problems later on since there are still outstanding RPC requests. I suspect that the early termination of blocked umount request will also now be broken now. Not sure what to do next here. Anyone want to volunteer some indepth detail on kernel RPC request termination on the issuing process receiving a TERM signal? >> >> >> >> >> >> 2009/8/17 Ian Kent : >>> On Thu, 2009-08-13 at 12:18 -0300, Carlos Andr=E9 wrote: >>>> Filled bug report: >>>> https://bugzilla.redhat.com/show_bug.cgi?id=3D517349 >>> Hi Carlos, >>> >>> I have a patched source rpm to add a mount wait parameter to autofs >>> located at: >>> http://people.redhat.com/~ikent/autofs-5.0.1-0.rc2.131.bz517349.1 >>> >>> Could you build it and see if it works. >>> I haven't tested it at all but it is fairly straight forward. >>> It is still unclear if this is the right way to do this and what the >>> consequences are in sending a term signal to mount. This mount request >>> will likely be followed by other requests for the same mount causing an >>> accumulation of mount(8) processes waiting for RPC timeouts before they >>> can answer the TERM signal. >>> >>> Anyway, for information the patch included in the source rpm above is: >>> >>> autofs-5.0.4 - add mount wait parameter >>> >>> From: Ian Kent >>> >>> Often delays when trying to mount from a server that is not reponding >>> for some reason are undesirable. To try and prevent these delays we >>> provide a configuration setting to limit the time that we wait for >>> our spawned mount(8) process to complete before sending it a SIGTERM >>> signal. This patch adds a configuration parameter to allow us to >>> request we limit the time we wait for mount(8) to complete before >>> send it a TERM signal. >>> --- >>> >>> daemon/spawn.c | 3 ++- >>> include/defaults.h | 2 ++ >>> lib/defaults.c | 13 +++++++++++++ >>> man/auto.master.5.in | 7 +++++++ >>> redhat/autofs.sysconfig.in | 9 +++++++++ >>> samples/autofs.conf.default.in | 9 +++++++++ >>> 6 files changed, 42 insertions(+), 1 deletion(-) >>> >>> >>> --- autofs-5.0.1.orig/daemon/spawn.c >>> +++ autofs-5.0.1/daemon/spawn.c >>> @@ -312,6 +312,7 @@ int spawn_mount(unsigned logopt, ...) >>> unsigned int options; >>> unsigned int retries =3D MTAB_LOCK_RETRIES; >>> int update_mtab =3D 1, ret, printed =3D 0; >>> + unsigned int wait =3D defaults_get_mount_wait(); >>> char buf[PATH_MAX]; >>> >>> /* If we use mount locking we can't validate the location */ >>> @@ -353,7 +354,7 @@ int spawn_mount(unsigned logopt, ...) >>> va_end(arg); >>> >>> while (retries--) { >>> - ret =3D do_spawn(logopt, -1, options, prog, (const char= **) argv); >>> + ret =3D do_spawn(logopt, wait, options, prog, (const ch= ar **) argv); >>> if (ret & MTAB_NOTUPDATED) { >>> struct timespec tm =3D {3, 0}; >>> >>> --- autofs-5.0.1.orig/include/defaults.h >>> +++ autofs-5.0.1/include/defaults.h >>> @@ -24,6 +24,7 @@ >>> >>> #define DEFAULT_TIMEOUT 600 >>> #define DEFAULT_NEGATIVE_TIMEOUT 60 >>> +#define DEFAULT_MOUNT_WAIT -1 >>> #define DEFAULT_UMOUNT_WAIT 12 >>> #define DEFAULT_BROWSE_MODE 1 >>> #define DEFAULT_LOGGING 0 >>> @@ -62,6 +63,7 @@ struct ldap_schema *defaults_get_schema( >>> struct ldap_searchdn *defaults_get_searchdns(void); >>> void defaults_free_searchdns(struct ldap_searchdn *); >>> unsigned int defaults_get_append_options(void); >>> +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); >>> --- autofs-5.0.1.orig/lib/defaults.c >>> +++ autofs-5.0.1/lib/defaults.c >>> @@ -45,6 +45,7 @@ >>> #define ENV_NAME_VALUE_ATTR "VALUE_ATTRIBUTE" >>> >>> #define ENV_APPEND_OPTIONS "APPEND_OPTIONS" >>> +#define ENV_MOUNT_WAIT "MOUNT_WAIT" >>> #define ENV_UMOUNT_WAIT "UMOUNT_WAIT" >>> #define ENV_AUTH_CONF_FILE "AUTH_CONF_FILE" >>> >>> @@ -323,6 +324,7 @@ unsigned int defaults_read_config(unsign >>> check_set_config_value(key, ENV_NAME_ENTRY_ATTR, val= ue, to_syslog) || >>> check_set_config_value(key, ENV_NAME_VALUE_ATTR, val= ue, to_syslog) || >>> check_set_config_value(key, ENV_APPEND_OPTIONS, valu= e, to_syslog) || >>> + check_set_config_value(key, ENV_MOUNT_WAIT, value, = to_syslog) || >>> check_set_config_value(key, ENV_UMOUNT_WAIT, value, = to_syslog) || >>> check_set_config_value(key, ENV_AUTH_CONF_FILE, valu= e, to_syslog) || >>> check_set_config_value(key, ENV_MAP_HASH_TABLE_SIZE,= value, to_syslog)) >>> @@ -652,6 +654,17 @@ unsigned int defaults_get_append_options >>> return res; >>> } >>> >>> +unsigned int defaults_get_mount_wait(void) >>> +{ >>> + long wait; >>> + >>> + wait =3D get_env_number(ENV_MOUNT_WAIT); >>> + if (wait < 0) >>> + wait =3D DEFAULT_MOUNT_WAIT; >>> + >>> + return (unsigned int) wait; >>> +} >>> + >>> unsigned int defaults_get_umount_wait(void) >>> { >>> long wait; >>> --- autofs-5.0.1.orig/man/auto.master.5.in >>> +++ autofs-5.0.1/man/auto.master.5.in >>> @@ -175,6 +175,13 @@ Set the default timeout for caching fail >>> 60). If the equivalent command line option is given it will override t= his >>> setting. >>> .TP >>> +.B MOUNT_WAIT >>> +Set the default time to wait for a response from a spawned mount(8) >>> +before sending it a SIGTERM. Note that we still need to wait for the >>> +RPC layer to timeout before the sub-process exits so this isn't ideal >>> +but it is the best we can do. The default is to wait until mount(8) >>> +returns without intervention. >>> +.TP >>> .B UMOUNT_WAIT >>> Set the default time to wait for a response from a spawned umount(8) >>> before sending it a SIGTERM. Note that we still need to wait for the >>> --- autofs-5.0.1.orig/redhat/autofs.sysconfig.in >>> +++ autofs-5.0.1/redhat/autofs.sysconfig.in >>> @@ -14,6 +14,15 @@ TIMEOUT=3D300 >>> # >>> #NEGATIVE_TIMEOUT=3D60 >>> # >>> +# MOUNT_WAIT - time to wait for a response from umount(8). >>> +# Setting this timeout can cause problems when >>> +# mount would otherwise wait for a server that >>> +# is temporarily unavailable, such as when it's >>> +# restarting. The defailt of waiting for mount(8) >>> +# usually results in a wait of around 3 minutes. >>> +# >>> +#MOUNT_WAIT=3D-1 >>> +# >>> # UMOUNT_WAIT - time to wait for a response from umount(8). >>> # >>> #UMOUNT_WAIT=3D12 >>> --- autofs-5.0.1.orig/samples/autofs.conf.default.in >>> +++ autofs-5.0.1/samples/autofs.conf.default.in >>> @@ -14,6 +14,15 @@ TIMEOUT=3D300 >>> # >>> #NEGATIVE_TIMEOUT=3D60 >>> # >>> +# MOUNT_WAIT - time to wait for a response from umount(8). >>> +# Setting this timeout can cause problems when >>> +# mount would otherwise wait for a server that >>> +# is temporarily unavailable, such as when it's >>> +# restarting. The defailt of waiting for mount(8) >>> +# usually results in a wait of around 3 minutes. >>> +# >>> +#MOUNT_WAIT=3D-1 >>> +# >>> # UMOUNT_WAIT - time to wait for a response from umount(8). >>> # >>> #UMOUNT_WAIT=3D12 >>> >>> >>>> Thanks! >>>> >>>> 2009/8/13 Carlos Andr=E9 : >>>>> 2009/8/13 Ian Kent : >>>>>> Carlos Andr=E9 wrote: >>>>>>> Today (2009-08-12) I'm using: >>>>>>> kernel-2.6.18-128.2.1.el5 >>>>>>> autofs-5.0.1-0.rc2.102.el5_3.1 >>>>>> Thanks, >>>>>> >>>>>> My mistake, the wait time I was referring to is used for umounts dur= ing >>>>>> expires and is present in rev rc2.102. >>>>>> >>>>>> It shouldn't be hard to add this for mount as well. >>>>>> Would you like me to put something together? >>>>> Sure! that 'll help me a lot (and for sure another ppl) :) Thanks :) >>>>> >>>>>> Probably would be good to test something out to see if we can make a >>>>>> difference with the killing mount after some configured timeout but,= if >>>>>> we make progress, probably the best way to deal with it is for you to >>>>>> log a bug against rhel-5 so I can get it committed to the rhel packa= ge. >>>>>> The possible issue is that I'm not sure if the RPC subsystem in the >>>>>> above rhel kernel will respond well to process death with potential >>>>>> outstanding requests. But we'll see. >>>>> Ok, on my way :) >>>>> >>>>> Thanks a lot! >>>>> >>>>>>> Look my last test: >>>>>>> -------------------------------------------------------------- >>>>>>> [root@KSTATION areas]# time ls testdown >>>>>>> ls: testdown: No such file or directory >>>>>>> >>>>>>> real 3m9.025s >>>>>>> user 0m0.000s >>>>>>> sys 0m0.002s >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> Aug 12 12:57:07 KSTATION automount[15471]: sun_mount: parse(sun): >>>>>>> mounting root /misc/areas, mountpoint testdown, what >>>>>>> 1.2.3.4:/areas/testdown, fstype nfs4, options >>>>>>> acl,sec=3Dkrb5p,proto=3Dtcp,retry=3D0 >>>>>>> Aug 12 12:57:07 KSTATION automount[15471]: do_mount: >>>>>>> 1.2.3.4:/areas/testdown /misc/areas/testdown type nfs4 options >>>>>>> acl,sec=3Dkrb5p,proto=3Dtcp,retry=3D0 using module nfs4 >>>>>>> Aug 12 12:57:07 KSTATION automount[15471]: mount_mount: mount(nfs): >>>>>>> root=3D/misc/areas name=3Dtestdown what=3D1.2.3.4:/areas/testdown, >>>>>>> fstype=3Dnfs4, options=3Dacl,sec=3Dkrb5p,proto=3Dtcp,retry=3D0 >>>>>>> Aug 12 12:57:07 KSTATION automount[15471]: mount_mount: mount(nfs): >>>>>>> nfs options=3D"acl,sec=3Dkrb5p,proto=3Dtcp,retry=3D0", nosymlink=3D= 0, ro=3D0 >>>>>>> Aug 12 12:57:07 KSTATION automount[15471]: mount_mount: mount(nfs): >>>>>>> calling mkdir_path /misc/areas/testdown >>>>>>> Aug 12 12:57:07 KSTATION automount[15471]: mount_mount: mount(nfs): >>>>>>> calling mount -t nfs4 -s -o acl,sec=3Dkrb5p,proto=3Dtcp,retry=3D0 >>>>>>> 1.2.3.4:/areas/testdown /misc/areas/testdown >>>>>>> Aug 12 12:58:12 KSTATION automount[15471]: st_expire: state 1 path = /misc >>>>>>> Aug 12 12:58:12 KSTATION automount[15471]: expire_proc: exp_proc = =3D >>>>>>> 3078093712 path /misc >>>>>>> Aug 12 12:58:13 KSTATION automount[15471]: expire_proc_indirect: 2 >>>>>>> submounts remaining in /misc >>>>>>> Aug 12 12:58:13 KSTATION automount[15471]: expire_cleanup: got thid >>>>>>> 3078093712 path /misc stat 3 >>>>>>> Aug 12 12:58:13 KSTATION automount[15471]: expire_cleanup: sigchld: >>>>>>> exp 3078093712 finished, switching from 2 to 1 >>>>>>> Aug 12 12:58:13 KSTATION automount[15471]: st_ready: st_ready(): st= ate >>>>>>> =3D 2 path /misc >>>>>>> Aug 12 12:59:28 KSTATION automount[15471]: st_expire: state 1 path = /misc >>>>>>> Aug 12 12:59:28 KSTATION automount[15471]: expire_proc: exp_proc = =3D >>>>>>> 3078093712 path /misc >>>>>>> Aug 12 12:59:28 KSTATION automount[15471]: expire_proc_indirect: 2 >>>>>>> submounts remaining in /misc >>>>>>> Aug 12 12:59:28 KSTATION automount[15471]: expire_cleanup: got thid >>>>>>> 3078093712 path /misc stat 3 >>>>>>> Aug 12 12:59:28 KSTATION automount[15471]: expire_cleanup: sigchld: >>>>>>> exp 3078093712 finished, switching from 2 to 1 >>>>>>> Aug 12 12:59:28 KSTATION automount[15471]: st_ready: st_ready(): st= ate >>>>>>> =3D 2 path /misc >>>>>>> Aug 12 13:00:16 KSTATION automount[15471]: >> mount: mount to NFS >>>>>>> server '1.2.3.4' failed: timed out (giving up). >>>>>>> Aug 12 13:00:16 KSTATION automount[15471]: mount(nfs): nfs: mount >>>>>>> failure 1.2.3.4:/areas/testdown on /misc/areas/testdown >>>>>>> Aug 12 13:00:16 KSTATION automount[15471]: send_fail: token =3D 17 >>>>>>> Aug 12 13:00:16 KSTATION automount[15471]: failed to mount /misc/ar= eas/testdown >>>>>>> Aug 12 13:00:43 KSTATION automount[15471]: st_expire: state 1 path = /misc >>>>>>> -------------------------------------------------------------- >>>>>>> >>>>>>> 2009/8/12 Ian Kent : >>>>>>>> Carlos Andr=E9 wrote: >>>>>>>>> Hi Ian, >>>>>>>>> I'm getting crazy trying put "retry=3D" to work on mount... this = option >>>>>>>>> just DONT WORK if use proto=3Dtcp and/OR kerberos (sec=3Dkrb5/krb= 5i/krb5p) >>>>>>>>> like you can see on my previous emails... >>>>>>>> Right, my mistake for not looking closely enough at post. >>>>>>>> >>>>>>>> Maybe this is related to the same sort of problem we had with moun= t in >>>>>>>> the past, before the options parsing went into the kernel, where o= ther >>>>>>>> services, like portmapper (or rpcbind), were being done with diffe= rent >>>>>>>> timeout parameters before the RPC calls for mounting. That's just = an >>>>>>>> example as NFSv4 shouldn't be sensitive to portmapper anyway. >>>>>>>> >>>>>>>> But what version of autofs and kernel did you say you were using? >>>>>>>> >>>>>>>>> I appreciate any help. >>>>>>>>> >>>>>>>>> Carlos. >>>>>>>>> >>>>>>>>> >>>>>>>>> 2009/8/12 Ian Kent : >>>>>>>>>> Chuck Lever wrote: >>>>>>>>>>> On Aug 11, 2009, at 8:41 AM, Carlos Andr=E9 wrote: >>>>>>>>>>>> This long timeout is good if workstation need mount a critical >>>>>>>>>>>> directory using /etc/fstab on boot (for example).. >>>>>>>>>>>> But in my case, using this loooong timeout doesnt make any sen= se, >>>>>>>>>>>> since autofs retry mount directory on-access. This in fact giv= es me >>>>>>>>>>>> alot of headaches, coz user login 'll just hangs if one server= goes >>>>>>>>>>>> down for any reason, and will again hangs if user try access d= irectory >>>>>>>>>>>> pointing to a NFS down server... >>>>>>>>>>> "retry=3D0" means the mount command will fail as soon as the fi= rst >>>>>>>>>>> mount(2) system call fails. When you set SYN retries to 1, thi= s means >>>>>>>>>>> after 9 seconds, the connect fails, and that causes the mount(2= ) system >>>>>>>>>>> call to fail. >>>>>>>>>>> >>>>>>>>>>> Recent conversations with Ian suggested that a long timeout was= desired >>>>>>>>>>> for automounter as well as other cases. Ian, is there somethin= g else we >>>>>>>>>>> need to consider to determine the correct retry timeout for NFS= /TCP >>>>>>>>>>> mount points handled via automounter? How should mount.nfs wai= t so we >>>>>>>>>>> don't make other use cases worse? (Looks like most of the hist= ory is >>>>>>>>>>> intact below). >>>>>>>>>> Of course we know that autofs is entirely at the mercy of mount(= 8) (and >>>>>>>>>> mount.nfs in particular). This has always been a difficult situa= tion for >>>>>>>>>> the automounter because interactive mount invocations should wai= t. But I >>>>>>>>>> believe automount mounts should always time out quickly, but tha= t leads >>>>>>>>>> to its own set of problems, especially when home directories are= concerned. >>>>>>>>>> >>>>>>>>>> I think adding "retry=3D0" is the right thing to do myself but I= 'm not >>>>>>>>>> certain that will work as we expect. I'll have to do some experi= mentation. >>>>>>>>>> >>>>>>>>>>> How long do you think is appropriate for the automounter to wai= t if the >>>>>>>>>>> server is down, in your case, Carlos? >>>>>>>>>>> >>>>>>>>>>>> Am losing something or there have was something weirdo...!? >>>>>>>>>>>> ------------------------------------------------ >>>>>>>>>>>> [root@KSTATION ~]# echo 5 > /proc/sys/net/ipv4/tcp_syn_retries= [DEFAULT] >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> proto=3Dtcp,retry=3D1 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 3m9.000s >>>>>>>>>>>> user 0m0.002s >>>>>>>>>>>> sys 0m0.001s >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> sec=3Dkrb5p,proto=3Dtcp,retry=3D1 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 3m9.000s >>>>>>>>>>>> user 0m0.000s >>>>>>>>>>>> sys 0m0.002s >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> proto=3Dtcp,retry=3D0 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 3m9.001s >>>>>>>>>>>> user 0m0.000s >>>>>>>>>>>> sys 0m0.003s >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> sec=3Dkrb5p,proto=3Dtcp,retry=3D0 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 3m9.001s >>>>>>>>>>>> user 0m0.002s >>>>>>>>>>>> sys 0m0.001s >>>>>>>>>>>> >>>>>>>>>>>> [root@KSTATION ~]# echo 1 > /proc/sys/net/ipv4/tcp_syn_retries= [ 5 to 1 ] >>>>>>>>>>>> >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> proto=3Dtcp,retry=3D1 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retryi= ng). [x 6] >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 1m3.002s >>>>>>>>>>>> user 0m0.000s >>>>>>>>>>>> sys 0m0.002s >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> sec=3Dkrb5p,proto=3Dtcp,retry=3D1 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retryi= ng). [x 13] >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 2m6.000s >>>>>>>>>>>> user 0m0.000s >>>>>>>>>>>> sys 0m0.002s >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> proto=3Dtcp,retry=3D0 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 0m9.003s >>>>>>>>>>>> user 0m0.001s >>>>>>>>>>>> sys 0m0.002s >>>>>>>>>>>> [root@KSTATION ~]# time mount 1.2.3.4:/blabla /tmp/ -t nfs4 -o >>>>>>>>>>>> sec=3Dkrb5p,proto=3Dtcp,retry=3D0 >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retryi= ng). [x 13] >>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (giving= up). >>>>>>>>>>>> >>>>>>>>>>>> real 2m6.001s >>>>>>>>>>>> user 0m0.001s >>>>>>>>>>>> sys 0m0.002s >>>>>>>>>>>> [root@KSTATION ~]# >>>>>>>>>>>> ------------------------------------------------ >>>>>>>>>>>> max timeout goes to 2m6s changing tcp_syn_retries from 5 to 1.= .. and >>>>>>>>>>>> using retry=3D0 without kerberos I got only 9s... >>>>>>>>>>>> >>>>>>>>>>>> *sigh* >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> 2009/8/10 Chuck Lever : >>>>>>>>>>>>> On Aug 10, 2009, at 4:05 PM, Carlos Andr=E9 wrote: >>>>>>>>>>>>>> Something funny: Using default tcp_syn_retries (5) i got >>>>>>>>>>>>>> "3,6,12,24,48,96" secs interval... but if i change tcp_syn_r= etries to >>>>>>>>>>>>>> 1 i got "3,6,3,6,3,6..." secs interval... >>>>>>>>>>>>> Right. Normally the RPC client calls the kernel's socket con= nect >>>>>>>>>>>>> function, >>>>>>>>>>>>> which does 6 SYN retries. That one call usually takes longer= than >>>>>>>>>>>>> the RPC >>>>>>>>>>>>> client's connect timeout, so it only makes one connect call, = and then >>>>>>>>>>>>> fails. >>>>>>>>>>>>> >>>>>>>>>>>>> Reducing the number of SYN retries per connect attempt causes= the RPC >>>>>>>>>>>>> client >>>>>>>>>>>>> to retry the connect call until its connect timeout expires. = Each >>>>>>>>>>>>> connect >>>>>>>>>>>>> call resets the SYN timeout to 3 seconds. >>>>>>>>>>>>> >>>>>>>>>>>>>> [root@KSERVER mnt]# time mount 1.2.3.4:/blabla tmp/ -t nfs4 = -o >>>>>>>>>>>>>> sec=3Dkrb5p,proto=3Dtcp >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (givi= ng up). >>>>>>>>>>>>>> >>>>>>>>>>>>>> real 3m9.000s >>>>>>>>>>>>>> user 0m0.000s >>>>>>>>>>>>>> sys 0m0.002s >>>>>>>>>>>>>> >>>>>>>>>>>>>> [root@KSERVER /]# echo 1 > /proc/sys/net/ipv4/tcp_syn_retries >>>>>>>>>>>>>> [root@KSERVER mnt]# time mount 1.2.3.4:/blabla tmp/ -t nfs4 = -o >>>>>>>>>>>>>> sec=3Dkrb5p,proto=3Dtcp ("retry=3D1" =3D no change) >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (retr= ying). >>>>>>>>>>>>>> mount: mount to NFS server '1.2.3.4' failed: timed out (givi= ng up). >>>>>>>>>>>>>> >>>>>>>>>>>>>> real 2m6.004s >>>>>>>>>>>>>> user 0m0.000s >>>>>>>>>>>>>> sys 0m0.004s >>>>>>>>>>>>>> >>>>>>>>>>>>>> (3,6,3,6... secs interval) >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2009/8/10 Carlos Andr=E9 : >>>>>>>>>>>>>>> No, i'm just using packages from CentOS repo... >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> And u're right about expo retries... with tcpdump i've moni= tored >>>>>>>>>>>>>>> traffic and i got SYN retries in 3, 6, 12, 24, 48, 96 secs = on port >>>>>>>>>>>>>>> 2049... >>>>>>>>>>>>>>> I tried use "retry=3D1" option on mount without any change.= .. I dont >>>>>>>>>>>>>>> want change source or tcp timers... just NFSv4 client. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> 2009/8/10 Chuck Lever : >>>>>>>>>>>>>>>> On Aug 10, 2009, at 2:29 PM, Carlos Andr=E9 wrote: >>>>>>>>>>>>>>>>> Bruce, no... you're right. I'm describing a situation wh= ere my >>>>>>>>>>>>>>>>> server >>>>>>>>>>>>>>>>> died... i need mount fail faster (10 or 15 secs max) than= 3 minutes >>>>>>>>>>>>>>>>> and 9 seconds... >>>>>>>>>>>>>>>> The 189 second timeout is likely how long it takes the ker= nel to >>>>>>>>>>>>>>>> give up >>>>>>>>>>>>>>>> trying to connect a TCP socket to the server (6 SYN attemp= ts with >>>>>>>>>>>>>>>> exponential retries, or something like that). For stock C= entOS >>>>>>>>>>>>>>>> 5.3, I >>>>>>>>>>>>>>>> think >>>>>>>>>>>>>>>> user space does only a DNS lookup for normal NFSv4 mounts = -- the >>>>>>>>>>>>>>>> kernel >>>>>>>>>>>>>>>> just >>>>>>>>>>>>>>>> tries to connect a TCP socket to port 2049, with no preced= ing rpcbind >>>>>>>>>>>>>>>> request. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Carlos, let us know if you have replaced any NFS-related C= entOS >>>>>>>>>>>>>>>> components >>>>>>>>>>>>>>>> (kernel, nfs-utils) with something you've built yourself. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 2009/8/7 J. Bruce Fields : >>>>>>>>>>>>>>>>>> On Fri, Aug 07, 2009 at 09:42:18AM +0300, Benny Halevy w= rote: >>>>>>>>>>>>>>>>>>> On Aug. 07, 2009, 3:18 +0300, Carlos Andr=E9 >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>>> Anyone ? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 2009/7/29 Carlos Andr=E9 : >>>>>>>>>>>>>>>>>>>>> PPL, I need put a CentOS 5.3 (updated) NFSv4 server t= o work with >>>>>>>>>>>>>>>>>>>>> Kerberos >>>>>>>>>>>>>>>>>>>>> and AutoFS, but i got a problem: If NFS server goes d= own i get a >>>>>>>>>>>>>>>>>>>>> LOOOOOOONG >>>>>>>>>>>>>>>>>>>>> mount timeout on CentOS 5.3 (updated) NFSv4 client... >>>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>> Since i need mount some (3 to 6) dirs at user logon p= rocess, if >>>>>>>>>>>>>>>>>>>>> mount >>>>>>>>>>>>>>>>>>>>> hangs, >>>>>>>>>>>>>>>>>>>>> user logon hangs. Then i want configure it to timeout= (if server >>>>>>>>>>>>>>>>>>>>> down) >>>>>>>>>>>>>>>>>>>>> after >>>>>>>>>>>>>>>>>>>>> 10-15 secs (MAX) on each mount attempt. >>>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>> I already make a lab and tried a LOT of combinations,= there my >>>>>>>>>>>>>>>>>>>>> findings >>>>>>>>>>>>>>>>>>>>> (server DOWN IP: 172.16.0.10 / client IP: 172.16.1.10= ) using >>>>>>>>>>>>>>>>>>>>> basic >>>>>>>>>>>>>>>>>>>>> command >>>>>>>>>>>>>>>>>>>>> (time mount 172.16.0.10:/remotedir /localdir/ -t nfs4= -o >>>>>>>>>>>>>>>>>>>>> sec=3Dkrb5,proto=3D) from NFS client: >>>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>> - Once i try access mount point using AutoFS (proto= =3Dtcp OR >>>>>>>>>>>>>>>>>>>>> proto=3Dudp) >>>>>>>>>>>>>>>>>>>>> it >>>>>>>>>>>>>>>>>>>>> hangs for 189 secs (3m9s: real 3m9.001s) until show= error >>>>>>>>>>>>>>>>>>>>> (mount: >>>>>>>>>>>>>>>>>>>>> mount to >>>>>>>>>>>>>>>>>>>>> NFS server '172.16.0.10' failed: timed out (giving up= )) >>>>>>>>>>>>>>>>>>> Sounds like you're hitting the server's grace period. >>>>>>>>>>>>>>>>>> I thought he was describing a situation where the server= the server >>>>>>>>>>>>>>>>>> is completely gone and isn't coming back, and wondering = how to make >>>>>>>>>>>>>>>>>> the >>>>>>>>>>>>>>>>>> mount fail faster. But I may be misunderstanding. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> --b. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>> To unsubscribe from this list: send the line "unsubscribe >>>>>>>>>>>>>>>>> linux-nfs" in >>>>>>>>>>>>>>>>> the body of a message to majordomo@vger.kernel.org >>>>>>>>>>>>>>>>> More majordomo info at http://vger.kernel.org/majordomo-= info.html >>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>> Chuck Lever >>>>>>>>>>>>>>>> chuck[dot]lever[at]oracle[dot]com >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>> -- >>>>>>>>>>>>> Chuck Lever >>>>>>>>>>>>> chuck[dot]lever[at]oracle[dot]com >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> Chuck Lever >>>>>>>>>>> chuck[dot]lever[at]oracle[dot]com >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> > = > =