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Hi,<BR><BR>
DRBD -Version 8.0.16 (Code for uuid_compare by rule 4 is same in all DRBD-8.x.y versions)<BR>
<BR>
We are consistently seeing content of snmpd.conf get corrupted -- sometimes it shows iptables and sometimes it has some wierd binary data.<BR>
<BR>
In all the instances we have seen corruption, Pattern observed from dmesg<BR>
uuid_compare()=0 by rule 4<BR>
No resync, but <FONT color=#ff0000><STRONG>78</STRONG> </FONT>bits in bitmap! <<<< Number of bits is variable. >>>><BR>
<BR>
>From drbd change log history we see that UUID_COMPARISON algorith was improved. <BR>
<BR>
* Sat Apr 07 2007 21:32:39 +0200 Philipp Reisner <phil(at)linbit.com><BR> - drbd (8.0.2-1)<BR> * Improved the robustness of the UUID based algorithm that decides about the resync direction.<BR><BR>
We would like to force sync in the rule 4 by doing the following, need your help in this regard.<BR>
case 0:<BR> /* !self_pri && !peer_pri */<BR> if (mdev->state.conn == WFBitMapT) {<BR> drbd_start_resync(mdev, SyncTarget);<BR> }<BR> else if (mdev->state.conn == WFBitMapS) {<BR> drbd_start_resync(mdev, SyncSource);<BR> }<BR> else if (mdev->state.conn == SyncTarget) {<BR> drbd_start_resync(mdev, SyncTarget);<BR> }<BR> else if (mdev->state.conn == SyncSource) {<BR> drbd_start_resync(mdev, SyncSource);<BR> }<BR> return 0;<BR>
<BR>
Testcase we are running:<BR>
Reset active board every 5 mins on a Redundant Setup.<BR>
<BR>
dmesg output:<BR>
11-02 22:10:23 unknown kernel drbd0: drbd_sync_handshake:<BR>11-02 22:10:23 unknown kernel drbd0: self 52A974873622A8A8:0000000000000000:D1A184CD02C8EE0D:BD9572546D8C332D<BR>11-02 22:10:23 unknown kernel drbd0: peer 77F8DC91C89BA0F9:52A974873622A8A8:D1A184CD02C8EE0C:BD9572546D8C332D<BR>11-02 22:10:23 unknown kernel drbd0: uuid_compare()=-1 by rule 5<BR>11-02 22:10:23 unknown kernel drbd0: peer( Unknown -> Primary ) conn( WFReportParams -> WFBitMapT ) pdsk( DUnknown -> UpToDate ) <BR>11-02 22:10:23 unknown kernel drbd0: conn( WFBitMapT -> WFSyncUUID ) <BR>11-02 22:10:23 unknown kernel drbd0: conn( WFSyncUUID -> SyncTarget ) disk( UpToDate -> Inconsistent ) <BR>11-02 22:10:23 unknown kernel drbd0: Began resync as SyncTarget (will sync 324 KB [81 bits set]).<BR>11-02 22:10:23 unknown kernel drbd0: Resync done (total 1 sec; paused 0 sec; 324 K/sec)<BR>11-02 22:10:23 unknown kernel drbd0: conn( SyncTarget -> Connected ) disk( Inconsistent -> UpToDate ) <BR>11-02 22:10:24 unknown kernel drbd0: local disk flush failed with status -95, disabling disk-flushes<BR>11-02 22:14:13 unknown kernel drbd0: peer( Primary -> Secondary ) <BR>11-02 22:14:14 unknown kernel drbd0: role( Secondary -> Primary ) <BR>11-02 22:14:14 unknown kernel EXT3 FS on drbd0, internal journal<BR>11-02 22:14:14 unknown kernel SELinux: initialized (dev drbd0, type ext3), uses xattr<BR>11-02 22:14:18 unknown kernel drbd0: peer( Secondary -> Unknown ) conn( Connected -> TearDown ) pdsk( UpToDate -> DUnknown ) <BR>11-02 22:14:18 unknown kernel drbd0: Creating new current UUID<BR>11-02 22:14:18 unknown kernel drbd0: meta connection shut down by peer.<BR>11-02 22:14:18 unknown kernel drbd0: asender terminated<BR>11-02 22:14:18 unknown kernel drbd0: Terminating asender thread<BR>11-02 22:14:19 unknown kernel drbd0: Connection closed<BR>11-02 22:14:19 unknown kernel drbd0: conn( TearDown -> Unconnected ) <BR>11-02 22:14:19 unknown kernel drbd0: receiver terminated<BR>11-02 22:14:19 unknown kernel drbd0: Restarting receiver thread<BR>11-02 22:14:19 unknown kernel drbd0: receiver (re)started<BR>11-02 22:14:19 unknown kernel drbd0: conn( Unconnected -> WFConnection ) <BR>11-02 22:15:16 unknown kernel drbd0: Handshake successful: DRBD Network Protocol version 86<BR>11-02 22:15:16 unknown kernel drbd0: conn( WFConnection -> WFReportParams ) <BR>11-02 22:15:16 unknown kernel drbd0: Starting asender thread (from drbd0_receiver [1495])<BR>11-02 22:15:16 unknown kernel drbd0: Considerable difference in lower level device sizes: 18768s vs. 32176s<BR>11-02 22:15:16 unknown kernel drbd0: drbd_sync_handshake:<BR>11-02 22:15:16 unknown kernel drbd0: self 77F8DC91C89BA0F9:77F8DC91C89BA0F9:A1454CD240FF75F4:52A974873622A8A8<BR>11-02 22:15:16 unknown kernel drbd0: peer 77F8DC91C89BA0F8:0000000000000000:A1454CD240FF75F4:52A974873622A8A8<BR>11-02 22:15:16 unknown kernel drbd0: uuid_compare()=0 by rule 4<BR>11-02 22:15:16 unknown kernel drbd0: No resync, but 78 bits in bitmap!<BR>11-02 22:15:16 unknown kernel drbd0: peer( Unknown -> Secondary ) conn( WFReportParams -> Connected ) pdsk( DUnknown -> UpToDate ) <BR>11-02 22:19:20 unknown kernel drbd0: role( Primary -> Secondary ) <BR>11-02 22:19:20 unknown kernel drbd0: peer( Secondary -> Unknown ) conn( Connected -> Disconnecting ) pdsk( UpToDate -> DUnknown ) <BR>
<BR>
<BR>LAK <BR><BR><BR><BR> </body>
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