Dell Unity: Sync Replication status Lost Sync Communication (0x840e)
Summary: Sync Replication was created successfully, but immediately it loses sync. Issue could be presented on either SPA or SPB or both SP's. (User Correctable)
Symptoms
FC zoning change was done to resolve crossed FC connections from SRC SP's to DR SP's.
- A sync replication session was created successfully, but immediately it loses sync.
- The issue could be seen on SPA or SPB or both SP's.
- When an issue is seen on only one SP, the session could be move to the other SP and it works fine.
Cause
- After reviewing FC connections it was found that the connections were crossed and modification of FC connection and zoning was redone to allow correct SPA <=> SPA, SPB <=> SPB connections.
- Even after the FC connections were fixed, without rebooting SP's on both SRC and DR the sync replication session still report lost sync communication. But the interconnection shows ok.
Resolution
With sync replication where FC connections and zoning were done, ensure to reboot both SP's on SRC and DR.
For your reference, the proposed changes are as follows - the following is updated in the future documentation for "Configuring Replication":
Zoning configuration
Ensure that you complete the following:
- Configure the port as an F-port to avoid any potential issues, and remove other types of ports from the list of allowed port types.
- For a synchronous replication connection, connect SPA port of the source system to the SPA port of the destination system. Similarly, the SPB port of the source system to the SPB port of the destination system
For example,
- OB_H1450 SPA Port 4 <--> OB_H1443 SPA Port 4
- OB_H1450 SPB Port 4 <--> OB_H1443 SPB Port 4
If Fibre Channel configuration is corrected from an incorrect cross configuration.
For example, the Fibre Channel configuration was cross-configured incorrectly:
- OB_H1450 SPA Port 4 <--> OB_H1443 SPB Port 4
- OB_H1450 SPB Port 4 <--> OB_H1443 SPA Port 4
Now, the configuration is corrected:
- OB_H1450 SPA Port 4 <--> OB_H1443 SPA Port 4
- OB_H1450 SPB Port 4 <--> OB_H1443 SPB Port 4
Ensure that you reboot both SP of both source system and destination system.
The SPA and SPB ports on the same side (source or destination) must have the identical port configuration. However, the configuration of ports on the source system can be different from the port configuration on the destination system. For example, SPA Port 4 <--> SPA I/O Module 0 Port 0 and SPB Port 4 <--> SPB I/O Module 0 Port 0 are supported.
Additional Information
Example: The following issue was seen only on a NAS Server Syn Replication on SPB where the FC connections topology is SRC FC switch <> Core FC switch <> DR FC switch.
SRC: APMxxx1 DR: APMxxx0 2: ID = RS_5 Name = unitySync Address = x.b.8.115 Alternate Management Address = x.b.8.115 Model = Unity 400 Serial number = APMxxx0 Connection type = sync Source interfaces = x.a.0.80, x.a.0.81 Local interfaces = x.a.0.80, x.a.0.81 Remote interfaces = x.b.8.130, x.b.8.131 Operational status = OK (0x2) Health state = OK (5) Health details = "Communication with the replication host is established. No action is required." Synchronous FC ports = spa_fc4, spb_fc4 | nasServer | x.x.x.2 x.x.x.2 | Not Configured | B | bond10 bond10 | 0x180000001B | 27 | 25 | TRUE | NFS | Name = rep_sess_nas_25_nas_34_APMxxx1_APMxxx0 Session type = nas server Synchronization type = sync RPO = N/A Resource type = NAS Server Sync State = out of sync Health state = Minor failure (15) Health details = "The connection with this remote replication host has been lost. On the Replication Connections page, click the Verify and Update Connection button. Operational status = Lost Sync Communication (0x840e) Source status = OK Destination status = OK Network status = Lost Sync communication Destination type = remote Destination system = RS_5 Local role = Source Source resource = nas_25 Source SP-A interface = x.a.0.80 Source SP-B interface = x.a.0.81 Destination resource = nas_34 Destination SP-A interface = x.b.8.130 Destination SP-B interface = x.b.8.131 Time of last sync = N/A Sync status = Sync transfer rate = N/A Sync transfer size remaining = N/A Previous transfer rate = N/A Average transfer rate = N/A Element pairs = N/A Hourly Snapshot Retention = Daily Snapshot Retention = Hourly snapshot keep for = Hourly snapshot allow auto-delete = Daily snapshot keep for = Daily snapshot allow auto-delete =
EMCSystemLogFile.log:
"2019-02-06T05:43:40.593Z" "Unity_spb" "Kittyhawk_safe" "17322" "unix/spb/root" "INFO" "1:1050207" :: "The minimum requirements for an active mirror have been met. Placing mirror 50060160c7e05f0d:3a000000000000xx in the active state automatically." :: Category=System Component=rmd
"2019-02-06T05:43:40.605Z" "Unity_spb" "Kittyhawk_safe" "17322" "unix/spb/root" "INFO" "1:1050210" :: "Full synchronization has started on image 50060160c7e068xx of the synchronous mirror with ID 50060160c7e05f0d:3a000000000000xx." :: Category=System Component=rmd
"2019-02-06T05:43:40.622Z" "Unity_spb" "Kittyhawk_safe" "17322" "unix/spb/root" "INFO" "1:1050401" :: "K10 50060160c7e068xx became unreachable." :: Category=System Component=rmd
"2019-02-06T05:43:40.633Z" "Unity_spb" "Kittyhawk_safe" "17322" "unix/spb/root" "INFO" "1:1050208" :: "The minimum requirements for an active mirror have not been met. Placing mirror 50060160c7e05f0d:3a00000000000xxx in the attention state automatically." :: Category=System Component=rmd
"2019-02-06T05:43:40.642Z" "Unity_spb" "Kittyhawk_safe" "17322" "unix/spb/root" "INFO" "1:105020c" :: "Image 50060160c7e068xx of the synchronous mirror with ID 50060160c7e05f0d:3a000000000000xx has been system fractured." :: Category=System Component=rmd
"2019-02-06T05:43:42.361Z" "Unity_spb" "Neo_CEM" "28673" "N/A" "ERROR" "14:6077e" :: "Replication session rep_sess_nas_36_nas_40_APMxxx1_APMxxx0 lost sync communication with its remote session" :: Category=User Component=Health
c4_safe_ktrace.log:
2019/02/06-05:43:23.361373 15K 7F239F8DC7xx std:RMD: Failed CMI transmission. CMI Ack Received Status = 0x7e11f061, mirror 103079215142_APMxxx1_0000_103079215144_APM00
2019/02/06-05:43:23.361375 ~~~~ 7F239F8DC7xx std:RMD: mAbortSync() called 103079215142_APMxxx1_0000_103079215144_APMxxx0_0000[6852]
2019/02/06-05:43:23.361377 ~~~~ 7F239F8DC7xx std:RMD: AbortSync Overlap 0 mirror 103079215142_APMxxx1_0000_103079215144_APMxxx0_0000
2019/02/06-05:43:23.361377 ~~~~ 7F239F8DC7xx std:RMD: mAbortSyncOperation() 103079215142_APMxxx1_0000_103079215144_APMxxx0_0000 [6852] 0/0
2019/02/06-05:43:23.361427 44 7F238C79E7xx std:RMD: Sys. Fracturing an image in syncQueue !!
2019/02/06-05:43:23.361428 ~~~~ 7F239F8DC7xx std:RMD: Released Sync Resource 0x7f199d3194xx for SyncIo 0x7f1a95c79d70 in mirror 103079215142_APMxxx1_0000_103079215144_AP
2019/02/06-05:43:23.361429 ~~~~ 7F238C79E7xx std:RMD: configPerformFracture called from line [2674] for mirror 103079215142_APMxxx1_0000_103079215xxx_APMxxx0_0000
2019/02/06-05:43:23.361781 346 7F2395E7Bxx std:PSMSYS:PSMSYS:psmDataAreaCloseCommit(001:014) DEFERRED for DW...
2019/02/06-05:43:23.361870 83 7F2395E7B7xx std:PSMSYS:PSMSYS:psmDataAreaCloseCommit(001:014) DEFERRED for WIP...
2019/02/06-05:43:23.361871 ~~~~ 7F2395E7B7xx std:PSMSYS:PSMSYS:psmDataAreaClose(1:14): PENDED...
2019/02/06-05:43:23.365851 3974 7F238C79E7xx std:RMD: Mirror 103079215142_APMxxx1_0000_103079215144_APMxxx0_0000 - Fracturing an already fractured slave
2019/02/06-05:43:23.365902 46 7F238C79E7xx std:RMD:mirrorFractureSlave: Aborting any pending Syncs for mirror(103079215142_APMxxx1_0000_103079215144_APMxxx0_000
2019/02/06-05:43:23.365903 ~~~~ 7F238C79E7xx std:RMD: mAbortSync() called 103079215142_APMxxx1_0000_103079215144_APMxxx0_0000[5872]
2019/02/06-05:43:23.365905 ~~~~ 7F238C79E7xx std:RMD: Aborted Pending Sync IO in CMI for mirror 103079215142_APMxxx1_0000_103079215144_APMxxx0_0000
2019/02/06-05:43:23.365906 ~~~~ 7F238C79E7xx std:RMD: Mirror 103079215142_APMxxx1_0000_103079215144_APMxxx0_0000 Image #1 has been fractured; 786432 bits in FL