Tag: ceph-mgr

HAProxy in front of Ceph Manager dashboard

The Ceph Mgr dashboard plugin allows for an easy dashboard which can show you how your Ceph cluster is performing.

In certain situations you can’t contact the Mgr daemons directly and you have to place a Proxy server between your computer and the Mgr daemons.

This can be done easily with HAProxy and the following configuration which assumes that:

  • SSL has been disabled in the Dashboard plugin
  • Dashboard plugin listens in port 8080
  • Mgr is running on the hosts mon01, mon02 and mon03
global
  log         127.0.0.1 local1
  log         127.0.0.1 local2 notice

  chroot      /var/lib/haproxy
  pidfile     /var/run/haproxy.pid
  maxconn     4000
  user        haproxy
  group       haproxy
  daemon

  stats socket /var/lib/haproxy/stats

defaults
  log                     global
  mode                    http
  retries                 3
  timeout http-request    10s
  timeout queue           1m
  timeout connect         10s
  timeout client          1m
  timeout server          1m
  timeout http-keep-alive 10s
  timeout check           10s
  maxconn                 3000
  option                  httplog
  no option               httpclose
  no option               http-server-close
  no option               forceclose

  stats enable
  stats hide-version
  stats refresh 30s
  stats show-node
  stats uri /haproxy?stats
  stats auth admin:haproxy

frontend https
  bind *:80
  default_backend ceph-dashboard

backend ceph-dashboard
  balance roundrobin
  option httpchk GET /
  http-check expect status 200
  server mon01 mon01:8080 check
  server mon02 mon02:8080 check
  server mon03 mon03:8080 check

You can now point your browser to the URL/IP of your HAProxy and use your Ceph dashboard.

In case a Mgr machine fails the health checks of HAProxy will make sure it fails over to on of the other Mgr daemons.

Using the new dashboard in ceph-mgr

The upcoming Ceph Luminous (12.2.0) release features the new ceph-mgr daemon which has a few default plugins. One of these plugins is a dashboard to give you a graphical overview of your cluster.

Enabling Module

To enable the dashboard you have to enable the module in your /etc/ceph/ceph.conf on all machines running the ceph-mgr daemon. These are usually your Monitors.

Add this to the configuration:

[mgr]
mgr_modules = dashboard

Don’t restart your ceph-mgr daemon yet. More configuration changes have to be made first.

Setting server address and port

A server address and optionally a port have to be configured as a config-key.

By setting the value to :: the dashboard will be available on all IPv4 and IPv6 addresses on port 7000 (default):

ceph config-key put mgr/dashboard/server_addr ::

Restart daemons

Now restart all ceph-mgr daemons on your hosts:

systemctl restart ceph-mgr@

Accessing the dashboard

The default port is 7000, so now go to the IP-Address of the active ceph-mgr and open the see the dashboard.

You can find the active ceph-mgr in the ceph status:

root@alpha:~# ceph -s
  cluster:
    id:     30d838cd-955f-42e5-bddb-5609e1c880f8
    health: HEALTH_OK
 
  services:
    mon: 3 daemons, quorum alpha,bravo,charlie
    mgr: charlie(active), standbys: alpha, bravo
    osd: 3 osds: 3 up, 3 in
 
  data:
    pools:   1 pools, 64 pgs
    objects: 0 objects, 0 bytes
    usage:   3173 MB used, 27243 MB / 30416 MB avail
    pgs:     64 active+clean
 
root@alpha:~#

In this case charlie is the active mgr which in my case has IPv6 Address 2001:db8::102.

Point your browser to: http://[2001:db8::102]:7000 and you will see the dashboard.