X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=sliver_libvirt.py;h=e898c4baa0fd3007ca5e7dec7160938a3be3ca44;hb=570d234b7d7b40416b296de71225f28c826ee991;hp=506ae0c818de8c27b6456d87ff9ab73db93a9453;hpb=ae9ce869dc1f25965dfd8107c88bfc7bcddcf3e2;p=nodemanager.git diff --git a/sliver_libvirt.py b/sliver_libvirt.py index 506ae0c..e898c4b 100644 --- a/sliver_libvirt.py +++ b/sliver_libvirt.py @@ -1,159 +1,294 @@ -# - """LibVirt slivers""" -import accounts -import logger +import sys +import os, os.path +import re import subprocess -import os -import os.path +import pprint +import random + import libvirt -import sys -import shutil -from string import Template +from account import Account +import logger +import plnode.bwlimit as bwlimit +import cgroups STATES = { - libvirt.VIR_DOMAIN_NOSTATE: 'no state', - libvirt.VIR_DOMAIN_RUNNING: 'running', - libvirt.VIR_DOMAIN_BLOCKED: 'blocked on resource', - libvirt.VIR_DOMAIN_PAUSED: 'paused by user', + libvirt.VIR_DOMAIN_NOSTATE: 'no state', + libvirt.VIR_DOMAIN_RUNNING: 'running', + libvirt.VIR_DOMAIN_BLOCKED: 'blocked on resource', + libvirt.VIR_DOMAIN_PAUSED: 'paused by user', libvirt.VIR_DOMAIN_SHUTDOWN: 'being shut down', - libvirt.VIR_DOMAIN_SHUTOFF: 'shut off', - libvirt.VIR_DOMAIN_CRASHED: 'crashed', + libvirt.VIR_DOMAIN_SHUTOFF: 'shut off', + libvirt.VIR_DOMAIN_CRASHED: 'crashed', } -REF_IMG_BASE_DIR = '/vservers/.lvref' -CON_BASE_DIR = '/vservers' +REASONS = { + libvirt.VIR_CONNECT_CLOSE_REASON_ERROR: 'Misc I/O error', + libvirt.VIR_CONNECT_CLOSE_REASON_EOF: 'End-of-file from server', + libvirt.VIR_CONNECT_CLOSE_REASON_KEEPALIVE: 'Keepalive timer triggered', + libvirt.VIR_CONNECT_CLOSE_REASON_CLIENT: 'Client requested it', +} connections = dict() -def getConnection(uri): - # TODO: error checking - return connections.setdefault(uri, libvirt.open(uri)) - -def create(name, xml, rec, conn): - ''' Create dirs, copy fs image, lxc_create ''' - logger.verbose ('sliver_libvirt: %s create'%(name)) - - # Get the type of image from vref myplc tags specified as: - # pldistro = lxc - # fcdistro = squeeze - # arch x86_64 - vref = rec['vref'] - if vref is None: - logger.log('sliver_libvirt: %s: WARNING - no vref attached defaults to lxc-debian' % (name)) - vref = "lxc-squeeze-x86_64" - - refImgDir = os.path.join(REF_IMG_BASE_DIR, vref) - containerDir = os.path.join(CON_BASE_DIR, name) - - # check the template exists -- there's probably a better way.. - if not os.path.isdir(refImgDir): - logger.log('sliver_libvirt: %s: ERROR Could not create sliver - reference image %s not found' % (name,vref)) - return - - # Copy the reference image fs - # shutil.copytree("/vservers/.lvref/%s"%vref, "/vservers/%s"%name, symlinks=True) - command = ['cp', '-r', refImgDir, containerDir] - logger.log_call(command, timeout=15*60) - - # Set hostname. A valid hostname cannot have '_' - with open(os.path.join(containerDir, 'etc/hostname'), 'w') as f: - print >>f, name.replace('_', '-') - - # Add slices group if not already present - command = ['/usr/sbin/groupadd', 'slices'] - logger.log_call(command, timeout=15*60) - - # Add unix account (TYPE is specified in the subclass) - command = ['/usr/sbin/useradd', '-g', 'slices', '-s', '/bin/sshsh', name, '-p', '*'] - logger.log_call(command, timeout=15*60) - command = ['mkdir', '/home/%s/.ssh'%name] - logger.log_call(command, timeout=15*60) - - # Create PK pair keys to connect from the host to the guest without - # password... maybe remove the need for authentication inside the - # guest? - command = ['su', '-s', '/bin/bash', '-c', 'ssh-keygen -t rsa -N "" -f /home/%s/.ssh/id_rsa'%(name)] - logger.log_call(command, timeout=15*60) - - command = ['chown', '-R', '%s.slices'%name, '/home/%s/.ssh'%name] - logger.log_call(command, timeout=15*60) - - command = ['cp', '/home/%s/.ssh/id_rsa.pub'%name, '%s/root/.ssh/authorized_keys'%containerDir] - logger.log_call(command, timeout=15*60) - - # Get a connection and lookup for the sliver before actually - # defining it, just in case it was already defined. - try: - dom = conn.lookupByName(name) - except: - dom = conn.defineXML(xml) - logger.verbose('lxc_create: %s -> %s'%(name, debuginfo(dom))) - - -def destroy(name, conn): - logger.verbose ('sliver_libvirt: %s destroy'%(name)) - - dir = '/vservers/%s'%(name) - lxc_log = '%s/lxc.log'%(dir) - - try: - - # Destroy libvirt domain - dom = conn.lookupByName(name) - dom.destroy() - dom.undefine() - - # Remove user after destroy domain to force logout - command = ['/usr/sbin/userdel', '-f', '-r', name] - logger.log_call(command, timeout=15*60) - - # Remove rootfs of destroyed domain - shutil.rmtree("/vservers/%s"%name) - except: - logger.verbose('sliver_libvirt: Unexpected error on %s: %s'%(name, sys.exc_info()[0])) - - -def start(dom): - ''' Just start the sliver ''' - print "LIBVIRT %s start"%(dom.name()) - - # Check if it's running to avoid throwing an exception if the - # domain was already running, create actually means start - if not is_running(dom): - dom.create() - else: - logger.verbose('sliver_libvirt: sliver %s already started'%(dom.name())) - - -def stop(dom): - logger.verbose('sliver_libvirt: %s stop'%(dom.name())) - - try: - dom.destroy() - except: - print "Unexpected error:", sys.exc_info()[0] - -def is_running(dom): - ''' Return True if the domain is running ''' - logger.verbose('sliver_libvirt: %s is_running'%dom.name()) - try: - [state, _, _, _, _] = dom.info() - if state == libvirt.VIR_DOMAIN_RUNNING: - logger.verbose('sliver_libvirt: %s is RUNNING'%(dom.name())) - return True +# Common Libvirt code + +class Sliver_Libvirt(Account): + + # Helper methods + + @staticmethod + def getConnection(sliver_type): + """ + returns a connection to the underlying libvirt service + a single connection is created and shared among slivers + this call ensures the connection is alive + and will reconnect if it appears to be necessary + """ + # sliver_type comes from rec['type'] and is of the form sliver.{LXC,QEMU} + # so we need to lower case to lxc/qemu + vtype = sliver_type.split('.')[1].lower() + uri = vtype + ':///' + if uri not in connections: + # create connection + conn = libvirt.open(uri) + connections[uri] = conn + return conn + else: + # connection already available : check for health + conn = connections[uri] + # see if a reconnection is needed + try: + numDomains = conn.numOfDomains() + except: + logger.log("libvirt connection to {} looks broken - reconnecting".format(uri)) + conn = libvirt.open(uri) + # if this fails then an expection is thrown outside of this function + numDomains = conn.numOfDomains() + return conn + + def __init__(self, rec): + self.name = rec['name'] + logger.verbose ('sliver_libvirt: {} init'.format(self.name)) + + # Assume the directory with the image and config files + # are in place + + self.keys = '' + self.rspec = {} + self.slice_id = rec['slice_id'] + self.enabled = True + self.conn = Sliver_Libvirt.getConnection(rec['type']) + self.xid = bwlimit.get_xid(self.name) + + dom = None + try: + dom = self.conn.lookupByName(self.name) + except: + logger.log('sliver_libvirt: Domain {} does not exist. ' \ + 'Will try to create it again.'.format(self.name)) + self.__class__.create(rec['name'], rec) + dom = self.conn.lookupByName(self.name) + self.dom = dom + + @staticmethod + def dom_details (dom): + output = "" + output += " id={} - OSType={}".format(dom.ID(), dom.OSType()) + # calling state() seems to be working fine + (state, reason) = dom.state() + output += " state={}, reason={}".format(STATES.get(state, state), + REASONS.get(reason, reason)) + try: + # try to use info() - this however does not work for some reason on f20 + # info cannot get info operation failed: Cannot read cputime for domain + [state, maxmem, mem, ncpu, cputime] = dom.info() + output += " [info: state={}, maxmem = {}, mem = {}, ncpu = {}, cputime = {}]"\ + .format(STATES.get(state, state), maxmem, mem, ncpu, cputime) + except: + # too bad but libvirt.py prints out stuff on stdout when this fails, don't know how to get rid of that.. + output += " [info: not available]" + return output + + def __repr__(self): + ''' Helper method to get a "nice" output of the domain struct for debug purposes''' + output = "Domain {}".format(self.name) + dom = self.dom + if dom is None: + output += " [no attached dom ?!?]" + else: + output += Sliver_Libvirt.dom_details (dom) + return output + + # Thierry : I am not quite sure if /etc/libvirt/lxc/<>.xml holds a reliably up-to-date + # copy of the sliver XML config; I feel like issuing a virsh dumpxml first might be safer + def repair_veth(self): + # See workaround email, 2-14-2014, "libvirt 1.2.1 rollout" + xmlfilename = "/etc/libvirt/lxc/{}.xml".format(self.name) + with open(xmlfilename) as xmlfile: + xml = xmlfile.read() + veths = re.findall("", xml) + veths = [x[13:-3] for x in veths] + for veth in veths: + command = ["ip", "link", "delete", veth] + logger.log_call(command) + + logger.log("trying to redefine the VM") + command = [ "virsh", "define", xmlfilename ] + logger.log_call(command) + + def start(self, delay=0): + '''Just start the sliver''' + logger.verbose('sliver_libvirt: {} start'.format(self.name)) + + # Check if it's running to avoid throwing an exception if the + # domain was already running + if not self.is_running(): + try: + # create actually means start + self.dom.create() + except Exception, e: + # XXX smbaker: attempt to resolve slivers that are stuck in + # "failed to allocate free veth". + if "ailed to allocate free veth" in str(e): + logger.log("failed to allocate free veth on {}".format(self.name)) + self.repair_veth() + logger.log("trying dom.create again") + self.dom.create() + else: + raise else: - info = debuginfo(dom) - logger.verbose('sliver_libvirt: %s is NOT RUNNING...\n%s'%(dom.name(), info)) - return False - except: - print "Unexpected error:", sys.exc_info() + logger.verbose('sliver_libvirt: sliver {} already started'.format(self.name)) + + # After the VM is started... we can play with the virtual interface + # Create the ebtables rule to mark the packets going out from the virtual + # interface to the actual device so the filter canmatch against the mark + bwlimit.ebtables("-A INPUT -i veth{} -j mark --set-mark {}" + .format(self.xid, self.xid)) + + ### this is confusing, because it seems it is not used in fact + def stop(self): + logger.verbose('sliver_libvirt: {} stop'.format(self.name)) + + # Remove the ebtables rule before stopping + bwlimit.ebtables("-D INPUT -i veth{} -j mark --set-mark {}" + .format(self.xid, self.xid)) + + try: + self.dom.destroy() + except: + logger.log_exc("in sliver_libvirt.stop", name=self.name) + + def is_running(self): + ''' Return True if the domain is running ''' + (state, _) = self.dom.state() + result = (state == libvirt.VIR_DOMAIN_RUNNING) + logger.verbose('sliver_libvirt.is_running: {} => {}' + .format(self, result)) + return result + + def configure(self, rec): + + #sliver.[LXC/QEMU] tolower case + #sliver_type = rec['type'].split('.')[1].lower() + + #BASE_DIR = '/cgroup/libvirt/{}/{}/'.format(sliver_type, self.name) + + # Disk allocation + # No way through cgroups... figure out how to do that with user/dir quotas. + # There is no way to do quota per directory. Chown-ing would create + # problems as username namespaces are not yet implemented (and thus, host + # and containers share the same name ids + + # Btrfs support quota per volumes + + if rec.has_key("rspec") and rec["rspec"].has_key("tags"): + if cgroups.get_cgroup_path(self.name) == None: + # If configure is called before start, then the cgroups won't exist + # yet. NM will eventually re-run configure on the next iteration. + # TODO: Add a post-start configure, and move this stuff there + logger.log("Configure: postponing tag check on {} as cgroups are not yet populated" + .format(self.name)) + else: + tags = rec["rspec"]["tags"] + # It will depend on the FS selection + if tags.has_key('disk_max'): + disk_max = tags['disk_max'] + if disk_max == 0: + # unlimited + pass + else: + # limit to certain number + pass + + # Memory allocation + if tags.has_key('memlock_hard'): + mem = str(int(tags['memlock_hard']) * 1024) # hard limit in bytes + cgroups.write(self.name, 'memory.limit_in_bytes', mem, subsystem="memory") + if tags.has_key('memlock_soft'): + mem = str(int(tags['memlock_soft']) * 1024) # soft limit in bytes + cgroups.write(self.name, 'memory.soft_limit_in_bytes', mem, subsystem="memory") + + # CPU allocation + # Only cpu_shares until figure out how to provide limits and guarantees + # (RT_SCHED?) + if tags.has_key('cpu_share'): + cpu_share = tags['cpu_share'] + cgroups.write(self.name, 'cpu.shares', cpu_share) + + # Call the upper configure method (ssh keys...) + Account.configure(self, rec) + + @staticmethod + def get_unique_vif(): + return 'veth{}'.format(random.getrandbits(32)) + + # A placeholder until we get true VirtualInterface objects + @staticmethod + def get_interfaces_xml(rec): + xml = """ + + + + +""".format(Sliver_Libvirt.get_unique_vif()) + try: + tags = rec['rspec']['tags'] + if 'interface' in tags: + interfaces = eval(tags['interface']) + if not isinstance(interfaces, (list, tuple)): + # if interface is not a list, then make it into a singleton list + interfaces = [interfaces] + tag_xml = "" + for interface in interfaces: + if 'vlan' in interface: + vlanxml = "".format(interface['vlan']) + else: + vlanxml = "" + if 'bridge' in interface: + tag_xml = tag_xml + """ + + + {} + + + + """.format(interface['bridge'], vlanxml, Sliver_Libvirt.get_unique_vif()) + else: + tag_xml = tag_xml + """ + + + + + """.format(Sliver_Libvirt.get_unique_vif()) -def debuginfo(dom): - ''' Helper method to get a "nice" output of the info struct for debug''' - [state, maxmem, mem, ncpu, cputime] = dom.info() - return '%s is %s, maxmem = %s, mem = %s, ncpu = %s, cputime = %s' % (dom.name(), STATES.get(state, state), maxmem, mem, ncpu, cputime) + xml = tag_xml + logger.log('sliver_libvirty.py: interface XML is: {}'.format(xml)) + except: + logger.log('sliver_libvirt.py: ERROR parsing "interface" tag for slice {}'.format(rec['name'])) + logger.log('sliver_libvirt.py: tag value: {}'.format(tags['interface'])) + return xml