下图显示了有ohasd管理的所有资源(resource)/守护进程(daemons)的依赖关系：
Diskmon
Master diskmon
• Monitors CELLSRVs and Network using Heartbeats
• Propagates Cell/Network state to ASM/RDBMS processes (dskm)
• Maintains a cluster-wide global view of Cells with other DISKMONs in the cluster
• Accepts fencing requests from CRS and delivers them to the Cells
• Accepts intradatabase IORM plans from RDBMS and sends them to the Cells
• Provides communication with the cells
Diskmon daemon用以监控Exadata 中的cell server，即只有在Exadata环境中才有用。但是在版本11.2.0.1-11.2.0.2，即便是非Exadata环境也会默认启动该守护进 程。 在版本11.2.0.3 中 改进了这一细节，非Exadata环境无发启动diskmon了。
11.2.0.3 Grid Infrastructure diskmon Will be Offline by Default in Non-Exadata Environment
What is being announced?
As Grid Infrastructure daemon diskmon.bin is used for Exadata fencing, started from 11.2.0.3, resource ora.diskmon will be offline in non-Exadata environment. This is expected behaviour change.
Prior to 11.2.0.3:
ps -ef| grep diskmon.bin
grid 3361 3166 0 22:57 ? 00:00:00 /ocw/grid/bin/diskmon.bin -d -f
On 11.2.0.3:
ps -ef| grep diskmon.bin
>> no more diskmon.bin
一些diskmon进程的日志：
[ CSSD]2009-07-27 10:27:36.419 [20] >TRACE: kgzf_dskm_conn4: unable to connect to master
diskmon in 60174 msec
[ CSSD]2009-07-27 10:27:36.419 [20] >TRACE: kgzf_send_main1: connection to master diskmon
timed out
[ CSSD]2009-07-27 10:27:36.421 [22] >TRACE: KGZF: Fatal diskmon condition, IO fencing is
not available. For additional error info look at the master diskmon log file (diskmon.log)
[ CSSD]2009-07-27 10:27:36.421 [22] >ERROR: ASSERT clsssc.c 2471
[ CSSD]2009-07-27 10:27:36.421 [22] >ERROR: clssscSAGEInitFenceCompl: Fence completion
failed, rc 56859
It seems that the new process registered with Oracle Clusterware diskmon is not able to communicate properly .
setsid: failed with -1/1
dskm_getenv_oracle_user: calling getpwnam_r for user oracle
dskm_getenv_oracle_user: info for user oracle complete
dskm_set_user: unable to change ownership for the log directory
/optware/oracle/11.1.0.7/crs/log/shplab01/diskmon to user oracle, id 1101, errno 1
07/27/09 10:27:37: Master Diskmon starting
The tusc output of the cssd log gives the following information
...
1248953770.528145 [/optware/ora][20944]{2992772}
unlink("/var/spool/sockets/pwgr/client20944") ERR#2 ENOENT
1248953770.612485 [/optware/ora][20944]{2992772}
unlink("/tmp/.oracle_master_diskmon") ERR#1 EPERM
1248953770.649479 [/optware/ora][20944]{2992772}
unlink("/tmp/.oracle_master_diskmon") ERR#1 EPERM
1248953770.656719 [/optware/ora][20944]{2992772}
unlink("/var/spool/sockets/pwgr/client20944") ERR#1 EPERM
...
There is a permission error of the file /tmp/.oracle_master_diskmon.
Solution
The resolution is to change the permissions of the file /tmp/.oracle_master_diskmon, which should be owned by oracle .
diskmon.log
============
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512] SKGXP:[386927568.6]{0}:
(14036 -> 12265) SKGXP_CHECK_HEART_BEAT_RESP_EXPIRE: NO PATH to Monitor
entry: 0x17161490
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512] SKGXP:[386927568.7]{0}:
Subnet: 0
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512] SKGXP:[386927568.8]{0}:
Remote endpoint [192.168.10.3/44538] is DOWN
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512] SKGXP:[386927568.9]{0}:
Local endpoint [192.168.10.1/45530] is UP
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512]
SKGXP:[386927568.10]{0}: SKGXP_DO_HEART_BEAT_RESP: Matching Monitor Entry Not
Found
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512]
SKGXP:[386927568.11]{0}: SKGXPGPID Internet address 192.168.10.3 RDS port
number 44538
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512] dskm_hb_thrd_main11:
got status change
2011-12-01 22:14:49.510: [ DISKMON][14036:1093384512]
dskm_ant_rsc_monitor_start: rscnam: o/192.168.10.3 rsc: 0x171609c0 state:
UNREACHABLE reconn_attempts: 0 last_reconn_ts: 1322773921
2011-12-01 22:14:49.649: [ DISKMON][14036:1093384512]
dskm_node_guids_are_offline: query SM done. retcode = 56891(REACHABLE)
2011-12-01 22:14:49.657: [ DISKMON][14036:1093384512] dskm_oss_get_net_info5:
oss_get_net_info for device o/192.168.10.3 returned skgxpid
040302010001894cb5afca0419ed706ae92f000008000000000000000000000001030000c0a80a
03000000000000000000000000adfa00000000000016000000 and the following 1 ip
adresess. known_reid: Yes
2011-12-01 22:14:49.657: [ DISKMON][14036:1093384512] 192.168.10.1
2011-12-01 22:14:49.657: [ DISKMON][14036:1093384512]
dskm_ant_rsc_monitor_start6.5:Cell does support TCP monitor, and does support
SM Query, cell incarnation is 1, guid num is 2
2011-12-01 22:14:49.657: [ DISKMON][14036:1093384512] GUID-0 =
0x0021280001a0af15
2011-12-01 22:14:49.657: [ DISKMON][14036:1093384512] GUID-1 =
0x0021280001a0af16
2011-12-01 22:14:49.657: [ DISKMON][14036:1093384512]
dskm_ant_rsc_monitor_start2: Connected to Same_Inc OSS device: o/192.168.10.3
numIP: 1
2011-12-01 22:14:49.657: [ DISKMON][14036:1093384512] 192.168.10.1
2011-12-01 22:15:07.501: [ DISKMON][14036:1108523328] dskm_slave_thrd_main3:
peer disconnected
2011-12-01 22:15:07.501: [ DISKMON][14036:1108523328] dskm_slave_thrd_main5:
client +ASM1/ASM/15374 disconnected, reid
cid=14e1b2b4de58ef1eff5487b58dccc906,icin=188142332,nmn=1,lnid=188142332,gid=7
,gin=1,gmn=0,umemid=0,opid=8,opsn=1,lvl=process hdr=0x 0
2011-12-01 22:15:08.440: [ CSSCLNT]clsssRecvMsg: got a disconnect from the
server while waiting for message type 1
2011-12-01 22:15:08.440: [ CSSCLNT]clssgsGroupGetStatus: communications
failed (0/3/-1)
2011-12-01 22:15:08.440: [ CSSCLNT]clssgsGroupGetStatus: returning 8
2011-12-01 22:15:08.440: [ DISKMON][14036:1102219584] CRITICAL: Diskmon
exiting: dskm_rac_thrd_main10: Diskmon is shutting down due to CSSD ABORT
event
2011-12-01 22:15:08.440: [ DISKMON][14036:1102219584] SHUTDOWN FORCE due to
CSSD ABORT
2011-12-01 22:15:08.440: [ DISKMON][14036:1102219584] dskm_rac_thrd_main:
exiting
2011-12-01 22:15:08.754: [ DISKMON][14036:1104320832] dskm_slave_thrd_main5:
client orarootagent/13701 disconnected, reid
cid=DUMMY,icin=-1,nmn=-1,lnid=-1,gid=-1,gin=-1,gmn=-1,umemid=-1,opid=-1,opsn=-
1,lvl=process hdr=0xfece0100
2011-12-01 22:15:09.988: [ DISKMON][14036:1191118288] dskm_cleanup_thrds:
cleaning up the rac event handling thread tid 1102219584
[ DISKMON][13016]
I/O Fencing and SKGXP HA monitoring daemon -- Version 1.2.0.0
Process 13016 started on 2011-12-01 at 22:15:39.863
2011-12-01 22:15:39.867: [ DISKMON][13016] dskm main: starting up
ocssd.log
==========
2011-12-01 22:15:04.223: [ CSSD][1127139648]clssgmmkLocalKillThread: Time
up. Timeout 60500 Start time 369099698 End time 369160198 Current time
369160198
2011-12-01 22:15:04.223: [ CSSD][1127139648]clssgmmkLocalKillResults:
Replying to kill request from remote node 2 kill id 1 Success map 0x00000000
Fail map 0x00000000
2011-12-01 22:15:04.224: [GIPCHAUP][1094015296] gipchaUpperProcessDisconnect:
processing DISCONNECT for hendp 0x2aa5550 [00000000000092e5] { gipchaEndpoint
: port 'nm2_gts-cluster/af9c-724c-2e3f-3946', peer
'gts1db02:205f-3cac-025e-c962', srcCid 00000000-000092e5, dstCid
00000000-000009d9, numSend 0, maxSend 100, usrFlags 0x4000, flags 0x204 }
2011-12-01 22:15:04.224: [ CSSD][1122408768]clssnmeventhndlr:
Disconnecting endp 0x932d ninf 0x1c3a2c0
2011-12-01 22:15:04.224: [ CSSD][1122408768]clssnmDiscHelper: gts1db02,
node(2) connection failed, endp (0x932d), probe(0x3000000000), ninf->endp
0x932d
2011-12-01 22:15:04.224: [ CSSD][1122408768]clssnmDiscHelper: node 2 clean
up, endp (0x932d), init state 3, cur state 3
2011-12-01 22:15:04.224: [GIPCXCPT][1122408768] gipcInternalDissociate: obj
0x2e99290 [000000000000932d] { gipcEndpoint : localAddr
'gipcha://gts1db01:nm2_gts-cluster/af9c-724c-2e3f-394', remoteAddr
'gipcha://gts1db02:205f-3cac-025e-c96', numPend 0, numReady 0, numDone 0,
numDead 0, numTransfer 0, objFlags 0x0, pidPeer 0, flags 0x13860e, usrFlags
0x0 } not associated with any container, ret gipcretFail (1)
2011-12-01 22:15:04.224: [GIPCXCPT][1122408768] gipcDissociateF
[clssnmDiscHelper : clssnm.c : 3284]: EXCEPTION[ ret gipcretFail (1) ]
failed to dissociate obj 0x2e99290 [000000000000932d] { gipcEndpoint :
localAddr 'gipcha://gts1db01:nm2_gts-cluster/af9c-724c-2e3f-394', remoteAddr
'gipcha://gts1db02:205f-3cac-025e-c96', numPend 0, numReady 0, numDone 0,
numDead 0, numTransfer 0, objFlags 0x0, pidPeer 0, flags 0x13860e, usrFlags
0x0 }, flags 0x0
2011-12-01 22:15:04.224: [GIPCXCPT][1122408768] gipcInternalDissociate: obj
0x2e99290 [000000000000932d] { gipcEndpoint : localAddr
'gipcha://gts1db01:nm2_gts-cluster/af9c-724c-2e3f-394', remoteAddr
'gipcha://gts1db02:205f-3cac-025e-c96', numPend 0, numReady 0, numDone 0,
numDead 0, numTransfer 0, objFlags 0x0, pidPeer 0, flags 0x13860e, usrFlags
0x0 } not associated with any container, ret gipcretFail (1)
2011-12-01 22:15:04.224: [GIPCXCPT][1122408768] gipcDissociateF
[clssnmDiscHelper : clssnm.c : 3430]: EXCEPTION[ ret gipcretFail (1) ]
failed to dissociate obj 0x2e99290 [000000000000932d] { gipcEndpoint :
localAddr 'gipcha://gts1db01:nm2_gts-cluster/af9c-724c-2e3f-394', remoteAddr
'gipcha://gts1db02:205f-3cac-025e-c96', numPend 0, numReady 0, numDone 0,
numDead 0, numTransfer 0, objFlags 0x0, pidPeer 0, flags 0x13860e, usrFlags
0x0 }, flags 0x0
2011-12-01 22:15:04.224: [ CSSD][1122408768]clssnmDiscEndp: gipcDestroy
0x932d
2011-12-01 22:15:04.603: [
CSSD][1104976192](:CSSNM00005:)clssnmvDiskKillCheck: Aborting, evicted by
node gts1db02, number 2, sync 188142334, stamp 393990918
2011-12-01 22:15:04.603: [
CSSD][1104976192]###################################
2011-12-01 22:15:04.603: [ CSSD][1104976192]clssscExit: CSSD aborting from
thread clssnmvKillBlockThread
2011-12-01 22:15:04.603: [
CSSD][1104976192]###################################
2011-12-01 22:15:04.603: [ CSSD][1104976192](:CSSSC00012:)clssscExit: A
fatal error occurred and the CSS daemon is terminating abnormally
gts1db01, number 1, has experienced a failure in thread number 10 and is
shutting down
2011-12-01 22:15:04.603: [ CSSD][1104976192]clssscExit: Starting CRSD
cleanup
2011-12-01 22:15:04.737: [ CSSD][1103399232]clssgmDiscEndpcl: gipcDestroy
0xa2ea2f7
2011-12-01 22:15:04.925: [
CSSD][1112947008](:CSSNM00058:)clssnmvDiskCheck: No I/O completions for
3472942430 ms for voting file o/192.168.10.5/DBFS_DG_CD_04_gts1cel03)
2011-12-01 22:15:04.925: [ CSSD][1112947008]clssnmvDiskAvailabilityChange:
voting file o/192.168.10.5/DBFS_DG_CD_04_gts1cel03 now offline
2011-12-01 22:15:04.925: [
CSSD][1112947008](:CSSNM00058:)clssnmvDiskCheck: No I/O completions for
3472942450 ms for voting file o/192.168.10.4/DBFS_DG_CD_02_gts1cel02)
2011-12-01 22:15:04.925: [ CSSD][1112947008]clssnmvDiskAvailabilityChange:
voting file o/192.168.10.4/DBFS_DG_CD_02_gts1cel02 now offline
2011-12-01 22:15:04.925: [
CSSD][1112947008](:CSSNM00058:)clssnmvDiskCheck: No I/O completions for
3472942480 ms for voting file o/192.168.10.3/DBFS_DG_CD_02_gts1cel01)
2011-12-01 22:15:04.926: [ CSSD][1112947008]clssnmvDiskAvailabilityChange:
voting file o/192.168.10.3/DBFS_DG_CD_02_gts1cel01 now offline
2011-12-01 22:15:04.926: [
CSSD][1112947008](:CSSNM00018:)clssnmvDiskCheck: Aborting, 0 of 3 configured
voting disks available, need 2
2011-12-01 22:15:04.926: [ CSSD][1112947008]clssscExit: abort already set
1
2011-12-01 22:15:04.926: [ SKGFD][1109793088]Lib :OSS:: closing handle
0x2538e70 for disk :o/192.168.10.5/DBFS_DG_CD_04_gts1cel03:
2011-12-01 22:15:04.926: [ SKGFD][1098676544]Lib :OSS:: closing handle
0x2aaaac0d7cb0 for disk :o/192.168.10.3/DBFS_DG_CD_02_gts1cel01:
Heartbeat timeout logic may to fail to detect dead cells if diskmon
has been running for over 40 days.
Rediscovery Notes:
If diskmon has been running for over 40 days and DB processes start to hang
after a cell death, you may have hit this bug.
All nodes may hang due to one of the heartbeat threads in diskmon
getting stuck trying to notify the instance(s) that it reconnected
to the cell. However if this occurs there is insufficient diagnostic
data collected to help confirm why the hang occurred.
This fix is a diagnostic enhancement for this scenario.
If diskmon/DSKM processes are hung/stuck this fix may help collect
additional useful diagnostics.
PROBLEM:
--------
Diskmon logs fill up quickly causing their disk / volume /u00 to become full
DIAGNOSTIC ANALYSIS:
--------------------
1) The following are consistently and repeatedly logged:
2010-12-17 03:22:25.848: [ DISKMON][17796:1089268032] dskm_rac_ini13: calling
clssgsqgrp
2010-12-17 03:22:25.849: [ DISKMON][17796:1089268032] dskm_rac_ini80: called
clssgsqgrp:
2010-12-17 03:22:25.849: [ DISKMON][17796:1089268032] dskm_dump_group_priv:
vers: 0 flags: 0x0 confInc: 0 My confInc: 0
2010-12-17 03:22:25.849: [ DISKMON][17796:1089268032] dskm_dump_group_priv:
CSS Msg Hdr: vers: 0 type: UNKNOWN (0) chunks: NO MORE CHUNKS (0) transport:
UNKNOWN (0) mSize: 0
2010-12-17 03:22:25.849: [ DISKMON][17796:1089268032] dskm_dump_group_priv:
Group Private Data is not of type DSKM_MSG_SS_REQ. Not proceeding with msg
dump
2010-12-17 03:22:25.849: [ DISKMON][17796:1089268032] dskm_rac_ini15: Found
my member number 1 to be busy. Waiting (attempts: 598) for OCSSD to clean up
previous incarnation
2) Core files generated, and many stack dumps of diskmon futher enlarges the
diskmon.log
The following is frequently seen in the diskmon.log
2010-12-17 03:22:28.855: [ DISKMON][17796:1089268032] dskm_rac_ini16: OCSSD
has notified that another diskmon is currently running in this node.
This might be a duplicate startup. If not consult OCSSD log for additional
information.
2010-12-17 03:22:28.855: [ DISKMON][17796] INCIDENT : EXCEPTION (SIGNAL: 6)
in [gsignal()]
2010-12-17 03:22:28.855: [ DISKMON][17796] Thread 1089268032 got exception 6
2010-12-17 03:22:28.855: [ DISKMON][17796] Stack dump for thread 1089268032
[ DISKMON][17796]
....
