[Cluster-devel] [PATCH] dlm: prompt the user SCTP is experimental

[Gang He]

Hi Steven and David,


>>> 
> Hi,
> 
> 
> On 09/04/18 06:02, Gang He wrote:
>> Hello David,
>>
>> If the user sets "protocol=tcp" in the configuration file /etc/dlm/dlm.conf 
> under two-rings cluster environment,
>> DLM kernel module will not work with the below error message,
>> [   43.696924] DLM installed
>> [  149.552039] ocfs2: Registered cluster interface user
>> [  149.559579] dlm: TCP protocol can't handle multi-homed hosts, try SCTP  
> <<== here, failed
>> [  149.559589] dlm: cannot start dlm lowcomms -22
>> [  149.559612] (mount.ocfs2,2593,3):ocfs2_dlm_init:3120 ERROR: status = -22
>> [  149.559629] (mount.ocfs2,2593,3):ocfs2_mount_volume:1845 ERROR: status = 
> -22
>>
>> Then, could we modify the code, let this case still work via only using one 
> ring address? or the code is written by purpose.
>> in lowcomms.c
>> 1358 static int tcp_listen_for_all(void)
>> 1359 {
>> 1360         struct socket *sock = NULL;
>> 1361         struct connection *con = nodeid2con(0, GFP_NOFS);
>> 1362         int result = -EINVAL;
>> 1363
>> 1364         if (!con)
>> 1365                 return -ENOMEM;
>> 1366
>> 1367         /* We don't support multi-homed hosts */
>> 1368         if (dlm_local_addr[1] != NULL) {   <<== here, could we get ride 
> of this limitation?
>> 1369                 log_print("TCP protocol can't handle multi-homed hosts, 
> "
>> 1370                           "try SCTP");
>> 1371                 return -EINVAL;
>> 1372         }
>> 1373
>> 1374         log_print("Using TCP for communications");
>> 1375
>> 1376         sock = tcp_create_listen_sock(con, dlm_local_addr[0]);
>> 1377         if (sock) {
>> 1378                 add_sock(sock, con);
>> 1379                 result = 0;
>> 1380         }
>> 1381         else {
>> 1382                 result = -EADDRINUSE;
>> 1383         }
>>
>>
>> Thanks
>> Gang
>>
> There is already a patch set to allow multi-homing for TCP. Mark and 
> Dave can comment on the current status and how far from merging it 
> currently is,
Thanks for your update on this problem, hopefully we can the related patches in the Linus git tree soon.

Thanks
Gang

> 
> Steve.