February 12, 2009"> 8"> gnt-cluster"> Debian"> GNU"> GPL"> ]> 2006 2007 2008 2009 Google Inc. &dhdate; &dhucpackage; &dhsection; ganeti 2.0 &dhpackage; ganeti administration, cluster-wide &dhpackage; command arguments... The &dhpackage; is used for cluster-wide administration in the ganeti system. add-tags --from file tag Add tags to the cluster. If any of the tags contains invalid characters, the entire operation will abort. If the --from option is given, the list of tags will be extended with the contents of that file (each line becomes a tag). In this case, there is not need to pass tags on the command line (if you do, both sources will be used). A file name of - will be interpreted as stdin. command -n node command Executes a command on all nodes. If the option -n is not given, the command will be executed on all nodes, otherwise it will be executed only on the node(s) specified. Use the option multiple times for running it on multiple nodes, like: # gnt-cluster command -n node1.example.com -n node2.example.com date The command is executed serially on the selected nodes. If the master node is present in the list, the command will be executed last on the master. Regarding the other nodes, the execution order is somewhat alphabetic, so that node2.example.com will be earlier than node10.example.com but after node1.example.com. So given the node names node1, node2, node3, node10, node11, with node3 being the master, the order will be: node1, node2, node10, node11, node3. The command is constructed by concatenating all other command line arguments. For example, to list the contents of the /etc directory on all nodes, run: # gnt-cluster command ls -l /etc and the command which will be executed will be "ls -l /etc" copyfile -n node file Copies a file to all or to some nodes. The argument specifies the source file (on the current system), the -n argument specifies the target node, or nodes if the option is given multiple times. If -n is not given at all, the file will be copied to all nodes. Example: # gnt-cluster -n node1.example.com -n node2.example.com copyfile /tmp/test This will copy the file /tmp/test from the current node to the two named nodes. destroy --yes-do-it Remove all configuration files related to the cluster, so that a gnt-cluster init can be done again afterwards. Since this is a dangerous command, you are required to pass the argument --yes-do-it. getmaster Displays the current master node. info Shows runtime cluster information: cluster name, architecture (32 or 64 bit), master node, node list and instance list. init -s secondary_ip -b bridge -g vg-name --master-netdev vg-name -m mac-prefix --no-lvm-storage --file-storage-dir dir --enabled-hypervisors hypervisors -t hypervisor name --hypervisor-parameters hypervisor:hv-param=value,hv-param=value --backend-parameters be-param=value,be-param=value clustername This commands is only run once initially on the first node of the cluster. It will initialize the cluster configuration and setup ssh-keys and more. Note that the clustername is not any random name. It has to be resolvable to an IP address using DNS, and it is best if you give the fully-qualified domain name. This hostname must resolve to an IP address reserved exclusively for this purpose. The cluster can run in two modes: single-home or dual-homed. In the first case, all traffic (both public traffic, inter-node traffic and data replication traffic) goes over the same interface. In the dual-homed case, the data replication traffic goes over the second network. The -s option here marks the cluster as dual-homed and its parameter represents this node's address on the second network. If you initialise the cluster with -s, all nodes added must have a secondary IP as well. Note that for Ganeti it doesn't matter if the secondary network is actually a separate physical network, or is done using tunneling, etc. For performance reasons, it's recommended to use a separate network, of course. The -b option specifies the default bridge for instances. The -g option will let you specify a volume group different than 'xenvg' for ganeti to use when creating instance disks. This volume group must have the same name on all nodes. Once the cluster is initialized this can be altered by using the modify command. If you don't want to use lvm storage at all use the --no-lvm-storage option. Once the cluster is initialized you can change this setup with the modify command. The --master-netdev option is useful for specifying a different interface on which the master will activate its IP address. It's important that all nodes have this interface because you'll need it for a master failover. The -m option will let you specify a three byte prefix under which the virtual MAC addresses of your instances will be generated. The prefix must be specified in the format XX:XX:XX and the default is aa:00:00. The --no-lvm-storage allows you to initialize the cluster without lvm support. This means that only instances using files as storage backend will be possible to create. Once the cluster is initialized you can change this setup with the modify command. The --file-storage-dir option allows you set the directory to use for storing the instance disk files when using file storage as backend for instance disks. The --enabled-hypervisors option allows you to set the list of hypervisors that will be enabled for this cluster. Instance hypervisors can only be choosen from the list of enabled hypervisors. Currently, the following hypervisors are available: xen-pvm Xen PVM hypervisor xen-hvm Xen HVM hypervisor kvm Linux KVM hypervisor fake fake hypervisor for development/testing Either a single hypervisor name or a comma-separated list of hypervisor names can be specified. If this option is not specified, only the xen-pvm hypervisor is enabled by default. With the -t option, the default hypervisor can be set. It has to be a member of the list of enabled hypervisors. If not specified, the first entry on the list of enabled hypervisors will be used by default. The --backend option allows you to set the default backend parameters for the cluster. The parameter format is a comma-separated list of key=value pairs with the following supported keys: vcpus Number of VCPUs to set for an instance by default, must be an integer, will be set to 1 if no specified. memory Amount of memory to allocate for an instance by default, can be either an integer or an integer followed by a unit (M for mebibytes and G for gibibytes are supported), will be set to 128M if not specified. auto_balance Value of the auto_balance flag for instances to use by default, will be set to true if not specified. The --hypervisor-parameters option allows you to set default hypervisor specific parameters for the cluster. The format of this option is the name of the hypervisor, followed by a colon and a comma-separated list of key=value pairs. The keys available for each hypervisors are detailed int the gnt-instance 8 man page, in the add command. list-tags List the tags of the cluster. masterfailover Failover the master role to the current node. modify -g vg-name --no-lvm-storage --enabled-hypervisors hypervisors --hypervisor-parameters hypervisor:hv-param=value,hv-param=value --backend-parameters be-param=value,be-param=value -C candidate_pool_size Modify the options for the cluster. The -g, --no-lvm-storarge, --enabled-hypervisors, --hypervisor-parameters and --backend-parameters options are described in the init command. The -C options specifies the candidate_pool_size cluster parameter. This is the number of nodes that the master will try to keep as master_candidates. For more details about this role and other node roles, see the ganeti7 . If you increase the size, the master will automatically promote as many nodes as required and possible to reach the intended number. queue drain undrain info Change job queue properties. The drain option sets the drain flag on the job queue. No new jobs will be accepted, but jobs already in the queue will be processed. The undrain will unset the drain flag on the job queue. New jobs will be accepted. The info option shows the properties of the job queue. redist-conf --submit This command forces a full push of configuration files from the master node to the other nodes in the cluster. This is normally not needed, but can be run if the verify complains about configuration mismatches. The --submit option is used to send the job to the master daemon but not wait for its completion. The job ID will be shown so that it can be examined via gnt-job info. remove-tags --from file tag Remove tags from the cluster. If any of the tags are not existing on the cluster, the entire operation will abort. If the --from option is given, the list of tags will be extended with the contents of that file (each line becomes a tag). In this case, there is not need to pass tags on the command line (if you do, both sources will be used). A file name of - will be interpreted as stdin. rename -f name Renames the cluster and in the process updates the master IP address to the one the new name resolves to. At least one of either the name or the IP address must be different, otherwise the operation will be aborted. Note that since this command can be dangerous (especially when run over SSH), the command will require confirmation unless run with the -f option. search-tags pattern Searches the tags on all objects in the cluster (the cluster itself, the nodes and the instances) for a given pattern. The pattern is interpreted as a regular expression and a search will be done on it (i.e. the given pattern is not anchored to the beggining of the string; if you want that, prefix the pattern with ^). If no tags are matching the pattern, the exit code of the command will be one. If there is at least one match, the exit code will be zero. Each match is listed on one line, the object and the tag separated by a space. The cluster will be listed as /cluster, a node will be listed as /nodes/name, and an instance as /instances/name. Example: # gnt-cluster search time /cluster ctime:2007-09-01 /nodes/node1.example.com mtime:2007-10-04 verify --no-nplus1-mem Verify correctness of cluster configuration. This is safe with respect to running instances, and incurs no downtime of the instances. If the --no-nplus1-mem option is given, ganeti won't check whether if it loses a node it can restart all the instances on their secondaries (and report an error otherwise). verify-disks The command checks which instances have degraded DRBD disks and activates the disks of those instances. This command is run from the ganeti-watcher tool, which also has a different, complementary algorithm for doing this check. Together, these two should ensure that DRBD disks are kept consistent. version Show the cluster version. &footer;