From: Brian Warner Date: Thu, 25 Sep 2008 00:47:16 +0000 (-0700) Subject: misc/make-canary-files.py: tool to create 'canary files', explained in the docstring X-Git-Url: https://git.rkrishnan.org/%5B/%5D%20/uri/%22file:/statistics?a=commitdiff_plain;h=1f9af40fd4a8ba7c91c572a4927e298406c6f545;p=tahoe-lafs%2Ftahoe-lafs.git misc/make-canary-files.py: tool to create 'canary files', explained in the docstring --- diff --git a/misc/make-canary-files.py b/misc/make-canary-files.py new file mode 100644 index 00000000..0baa6dd4 --- /dev/null +++ b/misc/make-canary-files.py @@ -0,0 +1,151 @@ +#! /usr/bin/python + +""" +Given a list of nodeids and a 'convergence' file, create a bunch of files +that will (when encoded at k=1,N=1) be uploaded to specific nodeids. + +Run this as follows: + + make-canary-files.py -c PATH/TO/convergence -n PATH/TO/nodeids -k 1 -N 1 + +It will create a directory named 'canaries', with one file per nodeid named +'$NODEID-$NICKNAME.txt', that contains some random text. + +The 'nodeids' file should contain one base32 nodeid per line, followed by the +optional nickname, like: + +--- +5yyqu2hbvbh3rgtsgxrmmg4g77b6p3yo server12 +vb7vm2mneyid5jbyvcbk2wb5icdhwtun server13 +... +--- + +The resulting 'canaries/5yyqu2hbvbh3rgtsgxrmmg4g77b6p3yo-server12.txt' file +will, when uploaded with the given (convergence,k,N) pair, have its first +share placed on the 5yyq/server12 storage server. If N>1, the other shares +will be placed elsewhere, of course. + +This tool can be useful to construct a set of 'canary' files, which can then +be uploaded to storage servers, and later downloaded to test a grid's health. +If you are able to download the canary for server12 via some tahoe node X, +then the following properties are known to be true: + + node X is running, and has established a connection to server12 + server12 is running, and returning data for at least the given file + +Using k=1/N=1 creates a separate test for each server. The test process is +then to download the whole directory of files (perhaps with a t=deep-check +operation). + +Alternatively, you could upload with the usual k=3/N=10 and then move/delete +shares to put all N shares on a single server. + +Note that any changes to the nodeid list will affect the placement of shares. +Shares should be uploaded with the same nodeid list as this tool used when +constructing the files. + +Also note that this tool uses the Tahoe codebase, so it should be run on a +system where Tahoe is installed, or in a source tree with setup.py like this: + + setup.py run_with_pythonpath -p -c 'misc/make-canary-files.py ARGS..' +""" + +import os, sha +from twisted.python import usage +from allmydata.immutable import upload +from allmydata.util import base32 + +class Options(usage.Options): + optParameters = [ + ("convergence", "c", None, "path to NODEDIR/private/convergence"), + ("nodeids", "n", None, "path to file with one base32 nodeid per line"), + ("k", "k", 1, "number of necessary shares, defaults to 1", int), + ("N", "N", 1, "number of total shares, defaults to 1", int), + ] + optFlags = [ + ("verbose", "v", "Be noisy"), + ] + +opts = Options() +opts.parseOptions() + +verbose = bool(opts["verbose"]) + +nodes = {} +for line in open(opts["nodeids"], "r").readlines(): + line = line.strip() + if not line or line.startswith("#"): + continue + pieces = line.split(None, 1) + if len(pieces) == 2: + nodeid_s, nickname = pieces + else: + nodeid_s = pieces[0] + nickname = None + nodeid = base32.a2b(nodeid_s) + nodes[nodeid] = nickname + +if opts["k"] != 3 or opts["N"] != 10: + print "note: using non-default k/N requires patching the Tahoe code" + print "src/allmydata/client.py line 55, DEFAULT_ENCODING_PARAMETERS" + +convergence_file = os.path.expanduser(opts["convergence"]) +convergence_s = open(convergence_file, "rb").read().strip() +convergence = base32.a2b(convergence_s) + +def get_permuted_peers(key): + results = [] + for nodeid in nodes: + permuted = sha.new(key + nodeid).digest() + results.append((permuted, nodeid)) + results.sort(lambda a,b: cmp(a[0], b[0])) + return [ r[1] for r in results ] + +def find_share_for_target(target): + target_s = base32.b2a(target) + prefix = "The first share of this file will be placed on " + target_s + "\n" + prefix += "This data is random: " + attempts = 0 + while True: + attempts += 1 + suffix = base32.b2a(os.urandom(10)) + if verbose: print " trying", suffix, + data = prefix + suffix + "\n" + assert len(data) > 55 # no LIT files + # now, what storage index will this get? + u = upload.Data(data, convergence) + eu = upload.EncryptAnUploadable(u) + d = eu.get_storage_index() # this happens to run synchronously + def _got_si(si): + if verbose: print "SI", base32.b2a(si), + peerlist = get_permuted_peers(si) + if peerlist[0] == target: + # great! + if verbose: print " yay!" + fn = base32.b2a(target) + if nodes[target]: + nickname = nodes[target].replace("/", "_") + fn += "-" + nickname + fn += ".txt" + fn = os.path.join("canaries", fn) + open(fn, "w").write(data) + return True + # nope, must try again + if verbose: print " boo" + return False + d.addCallback(_got_si) + # get sneaky and look inside the Deferred for the synchronous result + if d.result: + return attempts + +os.mkdir("canaries") +attempts = [] +for target in nodes: + target_s = base32.b2a(target) + print "working on", target_s + attempts.append(find_share_for_target(target)) +print "done" +print "%d attempts total, avg %d per target, max %d" % \ + (sum(attempts), 1.0* sum(attempts) / len(nodes), max(attempts)) + +