Bug 807213
Summary: | 'gluster volume status <vol_name> nfs client' command reports wrong message | ||
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Product: | [Community] GlusterFS | Reporter: | Shwetha Panduranga <shwetha.h.panduranga> |
Component: | cli | Assignee: | Kaushal <kaushal> |
Status: | CLOSED DEFERRED | QA Contact: | |
Severity: | medium | Docs Contact: | |
Priority: | medium | ||
Version: | mainline | CC: | divya, gluster-bugs |
Target Milestone: | --- | ||
Target Release: | --- | ||
Hardware: | Unspecified | ||
OS: | Unspecified | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | Bug Fix | |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | 2012-04-25 06:08:38 UTC | Type: | --- |
Regression: | --- | Mount Type: | --- |
Documentation: | DP | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: |
Description
Shwetha Panduranga
2012-03-27 10:02:46 UTC
I am assuming that the NFS server was restarted or something caused the NFS server to restart (like a graph change) once the NFS mounts were created. In this case, this output is expected because of the way the NFS server is designed. The NFS server is stateless, which means that it generally does not maintain any information regarding the clients connecting to it. It recieves and responds to the request as and when it gets them. The Gluster NFS server maintains a list of mounts, from which the "volume status" command extracts the clients list. Whenever the NFS server gets a new mount request, this list is updated with the new client. This list is updated and correct as long as the NFS server process is alive. If the process is killed and restarted this list gets reset to empty. NFS is designed in such a way that once clients have performed a mount, they can continue functioning without the need for a remount when a server process is restarted. Since a mount is not done again mountlist of the nfs server remains empty. Hence, the output of the "volume status" lists no clients. To fix this behavior will need a change to the NFS server itself. If my assumption was not the case, then I'll require more details. As explained by kaushal, the nfs client connections are not shown when the nfs server is restarted . This behavior is verified. [04/25/12 - 10:48:08 root@APP-SERVER1 ~]# gluster volume status dstore nfs client Client connections for volume dstore ---------------------------------------------- NFS Server : localhost Clients connected : 1 Hostname BytesRead BytesWritten -------- --------- ------------ 192.168.2.1:711 0 0 ---------------------------------------------- NFS Server : 192.168.2.36 Clients connected : 0 ---------------------------------------------- NFS Server : 192.168.2.37 Clients connected : 0 ---------------------------------------------- [04/25/12 - 10:48:10 root@APP-SERVER1 ~]# gluster volume set dstore stat-prefetch off Set volume successful [04/25/12 - 10:48:46 root@APP-SERVER1 ~]# gluster volume status dstore nfs client Client connections for volume dstore ---------------------------------------------- NFS Server : localhost Clients connected : 0 ---------------------------------------------- NFS Server : 192.168.2.36 Clients connected : 0 ---------------------------------------------- NFS Server : 192.168.2.37 Clients connected : 0 ---------------------------------------------- Closing this as deferred for now. This needs to be documented as a known issue. The documentation can be along the following lines, The client status for Gluster NFS-server is not always consistent, ie., 0 clients are displayed even when there are clients connected to the server. The client information is obtained from a mount list maintained by the NFS-server, which is a list of clients that have mounted shares exported by the server. This list is not maintained across server restarts, eg. when the server is restarted because of a graph change which occurs due to starting/stopping of a volume. Due to the stateless design of the NFS protocol, once a client mounts a share, it can continue its operations without performing a new mount when server restarts. This results in the Gluster NFS server mount list not containing the clients which connected earlier, leading to inconsistent client status for NFS servers. (PS: Not sure if the documentation needs to be so long) |