[heketi-devel] Unable to use Heketi setup to install Gluster for Kubernetes
Gaurav Chhabra
varuag.chhabra at gmail.com
Sat Sep 2 20:16:12 UTC 2017
Hi Jose,
webcenter/rancher-glusterfs-server is actually a container provided by
Sebastien, its maintainer. It's a Docker container which has GlusterFS
server running within it. On the host i.e., RancherOS, there is no separate
GlusterFS server running because we cannot install anything that way.
Running using container is the only way so i started
ancher-glusterfs-server container with the following parameters:
[root at node-1 rancher]# cat gluster-server.sh
#!/bin/bash
sudo docker run --name=gluster-server -d \
--env 'SERVICE_NAME=gluster' \
--restart always \
--publish 2222:22 \
webcenter/rancher-glusterfs-server
Here's the link to the dockerfile:
https://hub.docker.com/r/webcenter/rancher-glusterfs-server/~/dockerfile/
It's similar to other GlusteFS containers provided by other maintainers for
different OS. For example, for CentOS, we have
https://hub.docker.com/r/gluster/gluster-centos/~/dockerfile/
>From what i understand, Heketi does support container based GlusterFS
server as mentioned in the prerequisite
<https://github.com/gluster/gluster-kubernetes/blob/master/docs/setup-guide.md>
where it says:
"Each node must have the following ports opened for GlusterFS
communications:
2222 - GlusterFS pod's sshd"
That's the reason i've exposed port 2222 for 22 as shown above. Please
correct me if i misunderstood it.
As soon as i run the above script (gluster-server.sh), it automatically
creates the following directories on host. This should have ideally not
been empty as you mentioned.
/etc/glusterfs /var/lib/glusterd /var/log/glusterfs
Just wanted to know in which circumstances do we get this specific
error (Failed
to get D-Bus connection: Operation not permitted) related to Readiness
probe failing. Searching online took me to discussions
<https://serverfault.com/questions/824975/failed-to-get-d-bus-connection-operation-not-permitted>
around running container in *privileged* mode and some directory to be
mounted. Based on that, i also modified my container startup script to the
following:
#!/bin/bash
sudo docker run --privileged \
--name=gluster-server \
-d \
-v /sys/fs/cgroup:/sys/fs/cgroup \
-v /etc/glusterfs:/etc/glusterfs \
-v /var/lib/glusterd:/var/lib/glusterd \
-v /var/log/glusterfs:/var/log/glusterfs \
--env 'SERVICE_NAME=gluster' \
--restart always \
--publish 2222:22 \
webcenter/rancher-glusterfs-server
Still, the issue persists.
I also logged into the container and checked whether systemctl command is
present. It was there but manualy running the command also doesn't work:
[root at node-c ~]# docker exec -it gluster-server /bin/bash
root at 42150f203f80:/app# systemctl status glusterd.service
WARNING: terminal is not fully functional
Failed to connect to bus: No such file or directory
Under section 'ADVANCED OPTIONS - Security/Host' in this
<https://github.com/disaster37/rancher-glusterfs-server> link, it talks
about SYS_ADMIN setting. Any idea how i can try this?
Also, there was this mentioned in the Heketi setup
<https://github.com/gluster/gluster-kubernetes/blob/master/docs/setup-guide.md#infrastructure-requirements>
page:
"If you are not able to deploy a hyper-converged GlusterFS cluster, you
must have one running somewhere that the Kubernetes nodes can access"
>>> Does it mean running the three node Gluster cluster *outside*
Kubernetes, may be on some VM running on RHEL/CentOS etc? If yes, then *how*
will i be able to tell Gluster which volume from the Kubernetes cluster pod
to sync? Any references?
I really appreciate your responses despite the fact that you've not used
RancherOS but still trying to help.
Thanks,
Gaurav
On Sat, Sep 2, 2017 at 7:35 PM, Jose A. Rivera <jarrpa at redhat.com> wrote:
> I'm afraid I have no experience with RancherOS, so I may be missing
> some things about how it works. My primary experience is with Fedora,
> CentOS, and Ubuntu.
>
> What is webcenter/rancher-glusterfs-server? If it's running another
> glusterd then you probably don't want to be running it and should
> remove it from your systems.
>
> The glusterfs pods mount hostpath volumes from the host they're
> running on to persist their configuration. Thus anything they write to
> those directories should land on the host. If that's not happening
> then that's an additional problem.
>
> --Jose
>
> On Fri, Sep 1, 2017 at 11:17 PM, Gaurav Chhabra
> <varuag.chhabra at gmail.com> wrote:
> > Hi Jose,
> >
> >
> > I tried your suggestion but there is one confusion regarding point #3.
> Since
> > RancherOS has everything running as container, i am running
> > webcenter/rancher-glusterfs-server container on all three nodes. Now as
> far
> > as removing the directories are concerned, i hope you meant removing
> them on
> > the host and _not_ from within the container. After completing step 1
> and 2,
> > i checked the contents of all the directories that you specified in point
> > #3. All were empty as you can see in the attached other_logs.txt. So i
> got
> > confused. I ran the deploy again but the issue persists. Two pods show
> > Liveness error and the third one, Readiness error.
> >
> > I then tried removing those directories (Step #3) from within the
> container
> > but getting following error:
> >
> > root at c0f8ab4d92a2:/app# rm -rf /var/lib/heketi /etc/glusterfs
> > /var/lib/glusterd /var/log/glusterfs
> > rm: cannot remove '/var/lib/glusterd': Device or resource busy
> >
> >
> >
> > On Fri, Sep 1, 2017 at 8:21 PM, Jose A. Rivera <jarrpa at redhat.com>
> wrote:
> >>
> >> 1. Add a line to the ssh-exec portion of heketi.json of the sort:
> >>
> >> "sudo": true,
> >>
> >> 2. Run
> >>
> >> gk-deploy -g --abort
> >>
> >> 3. On the nodes that were/will be running GlusterFS pods, run:
> >>
> >> rm -rf /var/lib/heketi /etc/glusterfs /var/lib/glusterd
> /var/log/glusterfs
> >>
> >> Then try the deploy again.
> >>
> >> On Fri, Sep 1, 2017 at 6:05 AM, Gaurav Chhabra <
> varuag.chhabra at gmail.com>
> >> wrote:
> >> > Hi Jose,
> >> >
> >> >
> >> > Thanks for the reply. It seems the three gluster pods might have been
> a
> >> > copy-paste from another set of cluster where i was trying to setup the
> >> > same
> >> > thing using CentOS. Sorry for that. By the way, i did check for the
> >> > kernel
> >> > modules and it seems it's already there. Also, i am attaching fresh
> set
> >> > of
> >> > files because i created a new cluster and thought of giving it a try
> >> > again.
> >> > Issue still persists. :(
> >> >
> >> > In heketi.json, there is a slight change w.r.t the user which connects
> >> > to
> >> > glusterfs node using SSH. I am not sure how Heketi was using root user
> >> > to
> >> > login because i wasn't able to use root and do manual SSH. With
> rancher
> >> > user, i can login successfully so i think this should be fine.
> >> >
> >> > /etc/heketi/heketi.json:
> >> > ------------------------------------------------------------------
> >> > "executor": "ssh",
> >> >
> >> > "_sshexec_comment": "SSH username and private key file
> information",
> >> > "sshexec": {
> >> > "keyfile": "/var/lib/heketi/.ssh/id_rsa",
> >> > "user": "rancher",
> >> > "port": "22",
> >> > "fstab": "/etc/fstab"
> >> > },
> >> > ------------------------------------------------------------------
> >> >
> >> > Before running gk-deploy:
> >> > ------------------------------------------------------------------
> >> > [root at workstation deploy]# kubectl get
> >> > nodes,pods,daemonset,deployments,services
> >> > NAME STATUS AGE VERSION
> >> > no/node-a.c.kubernetes-174104.internal Ready 3h
> >> > v1.7.2-rancher1
> >> > no/node-b.c.kubernetes-174104.internal Ready 3h
> >> > v1.7.2-rancher1
> >> > no/node-c.c.kubernetes-174104.internal Ready 3h
> >> > v1.7.2-rancher1
> >> >
> >> > NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
> >> > svc/kubernetes 10.43.0.1 <none> 443/TCP 3h
> >> > ------------------------------------------------------------------
> >> >
> >> > After running gk-deploy:
> >> > ------------------------------------------------------------------
> >> > [root at workstation messagegc]# kubectl get
> >> > nodes,pods,daemonset,deployments,services
> >> > NAME STATUS AGE VERSION
> >> > no/node-a.c.kubernetes-174104.internal Ready 3h
> >> > v1.7.2-rancher1
> >> > no/node-b.c.kubernetes-174104.internal Ready 3h
> >> > v1.7.2-rancher1
> >> > no/node-c.c.kubernetes-174104.internal Ready 3h
> >> > v1.7.2-rancher1
> >> >
> >> > NAME READY STATUS RESTARTS AGE
> >> > po/glusterfs-0j9l5 0/1 Running 0 2m
> >> > po/glusterfs-gqz4c 0/1 Running 0 2m
> >> > po/glusterfs-gxvcb 0/1 Running 0 2m
> >> >
> >> > NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE
> >> > NODE-SELECTOR AGE
> >> > ds/glusterfs 3 3 0 3 0
> >> > storagenode=glusterfs 2m
> >> >
> >> > NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
> >> > svc/kubernetes 10.43.0.1 <none> 443/TCP 3h
> >> > ------------------------------------------------------------------
> >> >
> >> > Kernel module check on all three nodes:
> >> > ------------------------------------------------------------------
> >> > [root at node-a ~]# find /lib*/modules/$(uname -r) -name *.ko | grep
> >> > 'thin-pool\|snapshot\|mirror' | xargs ls -ltr
> >> > -rw-r--r-- 1 root root 92310 Jun 26 04:13
> >> > /lib64/modules/4.9.34-rancher/kernel/drivers/md/dm-thin-pool.ko
> >> > -rw-r--r-- 1 root root 56982 Jun 26 04:13
> >> > /lib64/modules/4.9.34-rancher/kernel/drivers/md/dm-snapshot.ko
> >> > -rw-r--r-- 1 root root 27070 Jun 26 04:13
> >> > /lib64/modules/4.9.34-rancher/kernel/drivers/md/dm-mirror.ko
> >> > -rw-r--r-- 1 root root 92310 Jun 26 04:13
> >> > /lib/modules/4.9.34-rancher/kernel/drivers/md/dm-thin-pool.ko
> >> > -rw-r--r-- 1 root root 56982 Jun 26 04:13
> >> > /lib/modules/4.9.34-rancher/kernel/drivers/md/dm-snapshot.ko
> >> > -rw-r--r-- 1 root root 27070 Jun 26 04:13
> >> > /lib/modules/4.9.34-rancher/kernel/drivers/md/dm-mirror.ko
> >> > ------------------------------------------------------------------
> >> >
> >> > Error snapshot attached.
> >> >
> >> > In my first mail, i checked that Readiness Probe failure check has
> this
> >> > code
> >> > in kube-templates/glusterfs-daemonset.yaml file:
> >> > ------------------------------------------------------------------
> >> > readinessProbe:
> >> > timeoutSeconds: 3
> >> > initialDelaySeconds: 40
> >> > exec:
> >> > command:
> >> > - "/bin/bash"
> >> > - "-c"
> >> > - systemctl status glusterd.service
> >> > periodSeconds: 25
> >> > successThreshold: 1
> >> > failureThreshold: 15
> >> > ------------------------------------------------------------------
> >> >
> >> > I tried logging into glustefs container on one of the node and ran the
> >> > above
> >> > command:
> >> >
> >> > [root at node-a ~]# docker exec -it c0f8ab4d92a23b6df2 /bin/bash
> >> > root at c0f8ab4d92a2:/app# systemctl status glusterd.service
> >> > WARNING: terminal is not fully functional
> >> > Failed to connect to bus: No such file or directory
> >> >
> >> >
> >> > Any check that i can do manually on nodes to debug further? Any
> >> > suggestions?
> >> >
> >> >
> >> > On Thu, Aug 31, 2017 at 6:53 PM, Jose A. Rivera <jarrpa at redhat.com>
> >> > wrote:
> >> >>
> >> >> Hey Gaurav,
> >> >>
> >> >> The kernel modules must be loaded on all nodes that will run heketi
> >> >> pods. Additionally, you must have at least three nodes specified in
> >> >> your topology file. I'm not sure how you're getting three gluster
> pods
> >> >> when you only have two nodes defined... :)
> >> >>
> >> >> --Jose
> >> >>
> >> >> On Wed, Aug 30, 2017 at 5:27 AM, Gaurav Chhabra
> >> >> <varuag.chhabra at gmail.com> wrote:
> >> >> > Hi,
> >> >> >
> >> >> >
> >> >> > I have the following setup in place:
> >> >> >
> >> >> > 1 node : RancherOS having Rancher application for Kubernetes
> setup
> >> >> > 2 nodes : RancherOS having Rancher agent
> >> >> > 1 node : CentOS 7 workstation having kubectl installed and folder
> >> >> > cloned/downloaded from https://github.com/gluster/
> gluster-kubernetes
> >> >> > using
> >> >> > which i run Heketi setup (gk-deploy -g)
> >> >> >
> >> >> > I also have rancher-glusterfs-server container running with the
> >> >> > following
> >> >> > configuration:
> >> >> > ------------------------------------------------------------------
> >> >> > [root at node-1 rancher]# cat gluster-server.sh
> >> >> > #!/bin/bash
> >> >> >
> >> >> > sudo docker run --name=gluster-server -d \
> >> >> > --env 'SERVICE_NAME=gluster' \
> >> >> > --restart always \
> >> >> > --env 'GLUSTER_DATA=/srv/docker/gitlab' \
> >> >> > --publish 2222:22 \
> >> >> > webcenter/rancher-glusterfs-server
> >> >> > ------------------------------------------------------------------
> >> >> >
> >> >> > In /etc/heketi/heketi.json, following is the only modified portion:
> >> >> > ------------------------------------------------------------------
> >> >> > "executor": "ssh",
> >> >> >
> >> >> > "_sshexec_comment": "SSH username and private key file
> >> >> > information",
> >> >> > "sshexec": {
> >> >> > "keyfile": "/var/lib/heketi/.ssh/id_rsa",
> >> >> > "user": "root",
> >> >> > "port": "22",
> >> >> > "fstab": "/etc/fstab"
> >> >> > },
> >> >> > ------------------------------------------------------------------
> >> >> >
> >> >> > Status before running gk-deploy:
> >> >> >
> >> >> > [root at workstation deploy]# kubectl get
> >> >> > nodes,pods,services,deployments
> >> >> > NAME STATUS AGE
> VERSION
> >> >> > no/node-1.c.kubernetes-174104.internal Ready 2d
> >> >> > v1.7.2-rancher1
> >> >> > no/node-2.c.kubernetes-174104.internal Ready 2d
> >> >> > v1.7.2-rancher1
> >> >> > no/node-3.c.kubernetes-174104.internal Ready 2d
> >> >> > v1.7.2-rancher1
> >> >> >
> >> >> > NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
> >> >> > svc/kubernetes 10.43.0.1 <none> 443/TCP 2d
> >> >> >
> >> >> >
> >> >> > Now when i run 'gk-deploy -g', in the Rancher console, i see the
> >> >> > following
> >> >> > error:
> >> >> > Readiness probe failed: Failed to get D-Bus connection: Operation
> not
> >> >> > permitted
> >> >> >
> >> >> > From the attached gk-deploy_log i see that it failed at:
> >> >> > Waiting for GlusterFS pods to start ... pods not found.
> >> >> >
> >> >> > In the kube-templates/glusterfs-daemonset.yaml file, i see this
> for
> >> >> > Readiness probe section:
> >> >> > ------------------------------------------------------------------
> >> >> > readinessProbe:
> >> >> > timeoutSeconds: 3
> >> >> > initialDelaySeconds: 40
> >> >> > exec:
> >> >> > command:
> >> >> > - "/bin/bash"
> >> >> > - "-c"
> >> >> > - systemctl status glusterd.service
> >> >> > periodSeconds: 25
> >> >> > successThreshold: 1
> >> >> > failureThreshold: 15
> >> >> > ------------------------------------------------------------------
> >> >> >
> >> >> >
> >> >> > Status after running gk-deploy:
> >> >> >
> >> >> > [root at workstation deploy]# kubectl get
> >> >> > nodes,pods,deployments,services
> >> >> > NAME STATUS AGE
> VERSION
> >> >> > no/node-1.c.kubernetes-174104.internal Ready 2d
> >> >> > v1.7.2-rancher1
> >> >> > no/node-2.c.kubernetes-174104.internal Ready 2d
> >> >> > v1.7.2-rancher1
> >> >> > no/node-3.c.kubernetes-174104.internal Ready 2d
> >> >> > v1.7.2-rancher1
> >> >> >
> >> >> > NAME READY STATUS RESTARTS AGE
> >> >> > po/glusterfs-0s440 0/1 Running 0 1m
> >> >> > po/glusterfs-j7dgr 0/1 Running 0 1m
> >> >> > po/glusterfs-p6jl3 0/1 Running 0 1m
> >> >> >
> >> >> > NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
> >> >> > svc/kubernetes 10.43.0.1 <none> 443/TCP 2d
> >> >> >
> >> >> >
> >> >> > Also, from prerequisite perspective, i was also seeing this
> >> >> > mentioned:
> >> >> >
> >> >> > The following kernel modules must be loaded:
> >> >> > * dm_snapshot
> >> >> > * dm_mirror
> >> >> > * dm_thin_pool
> >> >> >
> >> >> > Where exactly is this to be checked? On all Gluster server nodes?
> How
> >> >> > can i
> >> >> > check whether it's there?
> >> >> >
> >> >> > I have attached topology.json and gk-deploy log for reference.
> >> >> >
> >> >> > Does this issue has anything to do with the host OS (RancherOS)
> that
> >> >> > i
> >> >> > am
> >> >> > using for Gluster nodes? Any idea how i can fix this? Any help will
> >> >> > really
> >> >> > be appreciated.
> >> >> >
> >> >> >
> >> >> > Thanks.
> >> >> >
> >> >> >
> >> >> >
> >> >> > _______________________________________________
> >> >> > heketi-devel mailing list
> >> >> > heketi-devel at gluster.org
> >> >> > http://lists.gluster.org/mailman/listinfo/heketi-devel
> >> >> >
> >> >
> >> >
> >
> >
>
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