returning 127.0.0.2 for everything would be an ugly way to bow out.
yes, but it's been done before.
Someone has been in contact with Joe via phone and posted to another mailing list That Zhall Not Be Named that exactly that is happening. The zone is dead, he's put *.*.*.* in, he's asking people not to use it anymore. It may be back in the future with a new network setup, but right now consider it down. We're working on getting him to send out a public announcement. Yes, this is due to a massive DDOS. At least three of the spamfilter BLs have been so attacked this week. Some of the networks represented here have not been as timely about helping the BL providers with the DDOSes as they could be. Please keep in mind that without dynamic BLs anti-spam folks will fall back to sending out static block maps, which getting your IP space out of will be difficult if not impossible. IT IS VERY MUCH IN NETWORK OPERATORS BEST INTEREST THAT THIS NOT HAPPEN. Please take what measures are necessary to help ensure that your customers are not intentionally or neglegently DDOSing the BLs. -george william herbert gherbert@retro.com
George William Herbert wrote:
Yes, this is due to a massive DDOS. At least three of the spamfilter BLs have been so attacked this week.
Some of the networks represented here have not been as timely about helping the BL providers with the DDOSes as they could be. Please keep in mind that without dynamic BLs anti-spam folks will fall back to sending out static block maps, which getting your IP space out of will be difficult if not impossible.
IT IS VERY MUCH IN NETWORK OPERATORS BEST INTEREST THAT THIS NOT HAPPEN.
Please take what measures are necessary to help ensure that your customers are not intentionally or neglegently DDOSing the BLs.
Well said George, I have been one of the recepients of the DDoS attacks. If people see non DNS UDP traffic or non Type 3 ICMP traffic aimed at 203.15.51.32/27 it is likely DDoS traffic. Currently I still have at least one IP in that range Null Routed by upstreams. SORBS may have to implement a subscription model soon to fund more hosts around the world if the DDoS's continue, I am desperately trying to avoid it, should it become nessessary it will be for the +50k queries/day users out there. The point is SORBS is funded soley by myself and through hosting dontations - I have 5 public secondaries donated currently, and I cannot afford, personally, any DDoS proofing other than that I have now. I know of at least 3 other DNSbls that are experiencing DDoS issues, and one DNSbl operator that is scared stiff of DDoS. Yours Mat Note: If anyone wants to talk about SORBS, public secondaries, donations, policy etc... this is not the forum, please contact me off list.
On 8/26/03 4:45 PM, "Matthew Sullivan" <matthew@sorbs.net> wrote:
George William Herbert wrote:
Yes, this is due to a massive DDOS. At least three of the spamfilter BLs have been so attacked this week.
Some of the networks represented here have not been as timely about helping the BL providers with the DDOSes as they could be. Please keep in mind that without dynamic BLs anti-spam folks will fall back to sending out static block maps, which getting your IP space out of will be difficult if not impossible.
IT IS VERY MUCH IN NETWORK OPERATORS BEST INTEREST THAT THIS NOT HAPPEN.
Please take what measures are necessary to help ensure that your customers are not intentionally or neglegently DDOSing the BLs.
Well said George,
I have been one of the recepients of the DDoS attacks. If people see non DNS UDP traffic or non Type 3 ICMP traffic aimed at 203.15.51.32/27 it is likely DDoS traffic. Currently I still have at least one IP in that range Null Routed by upstreams.
SORBS may have to implement a subscription model soon to fund more hosts around the world if the DDoS's continue, I am desperately trying to avoid it, should it become nessessary it will be for the +50k queries/day users out there. The point is SORBS is funded soley by myself and through hosting dontations - I have 5 public secondaries donated currently, and I cannot afford, personally, any DDoS proofing other than that I have now. I know of at least 3 other DNSbls that are experiencing DDoS issues, and one DNSbl operator that is scared stiff of DDoS.
Yours
Mat
Note: If anyone wants to talk about SORBS, public secondaries, donations, policy etc... this is not the forum, please contact me off list.
Hello: If you and others are experiencing DDOS attacks it would be a good idea to get the affected IP's on to the various lists associated with the tracking of such events. If you would like me to post them, I would be happy to do so. Please let me know the IP blocks, other than the one mentioned above, and I will post them to the lists. Thanks, Mike -- Michael K. Smith NoaNet 206.219.7116 (work) 206.579.8360 (cell) mksmith@noanet.net http://www.noanet.net
ok so this part does not mystify me...
Someone has been in contact with Joe via phone and posted to another mailing list That Zhall Not Be Named that exactly that is happening. The zone is dead, ...
...because running blackhole lists is surprisingly more hard than most people think. (witness the sorbs.net message here a few hours ago complaining of 50Kpkt/day query loads.) i've paid some dues in this area, so i feel qualified to say that "i told you so" on this topic. but at least there's no mystery. this part, on the other hand...
he's put *.*.*.* in, he's asking people not to use it anymore.
...mystifies me. anyone who has read rfc1034 or rfc1035, even if they did not also read rfc2181 or rfc2136 or rfc2308, knows that in a zone containing the following wildcardish data: $ORIGIN example.vix.com. * 1H IN A 127.0.0.1 *.* 1H IN A 127.0.0.2 *.*.* 1H IN A 127.0.0.3 *.*.*.* 1H IN A 127.0.0.4 the result will be that only the top one will match: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 16926 ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 0 ;; QUERY SECTION: ;; 40.30.20.10.example.vix.com, type = A, class = IN ;; ANSWER SECTION: 40.30.20.10.example.vix.com. 1H IN A 127.0.0.1 and that in a zone containing only this data: $ORIGIN example.vix.com. *.*.*.* 1H IN A 127.0.0.4 the result will be that none of them ever match: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 44811 ;; flags: qr aa rd; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0 ;; QUERY SECTION: ;; 40.30.20.10.example.vix.com, type = A, class = IN you don't even need to read draft-ietf-dnsext-wcard-clarify-01.txt to know that putting "*.*.*.*" into a zone won't actually mean, or do, *anything*.
It may be back in the future with a new network setup, but right now consider it down.
i'm not completely sure, but i don't think this list will see much action in the future from the sysadmins who had to make emergency config changes today to avoid bouncing all their e-mail. "once burned, twice shy," eh? when i deprecated the old $foo.maps.vix.com zones in favour of the their corresponding replacements $bar.mail-abuse.org some years ago, i had the foresight to ensure that no mail would be blocked by people who failed to put in the configuration change. now you can all see why that was nec'y. -- Paul Vixie
On 27 Aug 2003, Paul Vixie wrote:
...because running blackhole lists is surprisingly more hard than most people think. (witness the sorbs.net message here a few hours ago complaining of 50Kpkt/day query loads.) i've
Matt wasn't complaining about query loads. And 50Kpkt/day in queries is nothing anyway. He was complaining about being DDoS'd by spammers or others who just don't like dnsbls. AFAIK, SORBS, SPEWS, and Osirusoft have all been the targets of DDoS's for a few weeks.
this part, on the other hand...
he's put *.*.*.* in, he's asking people not to use it anymore.
...mystifies me. anyone who has read rfc1034 or rfc1035, even if they did not also read rfc2181 or rfc2136 or rfc2308, knows that in a zone containing the following wildcardish data:
$ORIGIN example.vix.com. * 1H IN A 127.0.0.1 *.* 1H IN A 127.0.0.2
This was just a misunderstanding on the part of the previous poster. Unless he has a copy of the zone (not likely given the unreliability of Joe's DNS servers lately), he wouldn't be able to see this. I think he just wasn't familiar with how wildcards worked and assumed each * only matched one [^.]*, which is incorrect. AFAICT, what he did add was: * 24H A 127.0.0.2 24H TXT "Please stop using relays.osirusoft.com" which is much worse than just emptying the zone, removing it from the NS's, or shutting down the DNS servers.
when i deprecated the old $foo.maps.vix.com zones in favour of the their corresponding replacements $bar.mail-abuse.org some years ago, i had the foresight to ensure that no mail would be blocked by people who failed to put in the configuration change. now you can all see why that was nec'y.
Mail would only have been blocked if you had done something crazy like the above. Mail was delayed (and servers put under heavy load waiting for DNS queries to time out) when MAPS finally shut off free access without warning (a week or more after they originally had warned they'd do it, but gave everyone an extension when there was massive public outcry and they were unable to keep up with inquiries about buying access). ---------------------------------------------------------------------- Jon Lewis *jlewis@lewis.org*| I route System Administrator | therefore you are Atlantic Net | _________ http://www.lewis.org/~jlewis/pgp for PGP public key_________
--On Wednesday, August 27, 2003 7:53 AM -0400 jlewis@lewis.org wrote:
Mail was delayed (and servers put under heavy load waiting for DNS queries to time out) when MAPS finally shut off free access without warning (a week or more after they originally had warned they'd do it, but gave everyone an extension when there was massive public outcry and they were unable to keep up with inquiries about buying access).
Point of clarification - In early to mid July, we gave notice we were securing the zones at the end of July. Starting August 1 we used "deny" ACLs based on the IP addresses making the largest number of queries - and we emailed domain contacts for those. The "deny" ACL was not changed to an "allow" ACL until October 1 - over 10 weeks after we announced the zones would close. That is hardly "without warning", nor was it because of public outcry. (The part about not being able to keep up with inquiries was definitely true, but I did learn that sleep is highly overrated <g>.) At no time did we return positive answers for IP addresses that were not listed. Two years after the fact, we *still* get tens of thousands of queries a day from IP addresses that are not subscribed. -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= -=-= Margie Arbon Mail Abuse Prevention System, LLC margie@mail-abuse.org http://mail-abuse.org
Ok this time with the correct from address ;-) Paul Vixie wrote:
ok so this part does not mystify me...
Someone has been in contact with Joe via phone and posted to another mailing list That Zhall Not Be Named that exactly that is happening. The zone is dead, ...
...because running blackhole lists is surprisingly more hard than most people think. (witness the sorbs.net message here a few hours ago complaining of 50Kpkt/day query loads.) i've paid some dues in this area, so i feel qualified to say that "i told you so" on this topic. but at least there's no mystery.
I'm not worried about the 50k queries a day, the previous mail was about setting this a threshold as a 'ok you're saving some money/bandwidth by using us, help us extend the service and protect against DDoS by paying a nominal subscription' I can handle around 6000 DNS queries per second here, but the DDoS hit the servers with 300,000 packets per second of invalid DDoS crap that I can't handle alone. I have been talking to a lot of people about solutions and came up with a 'distributed DNS blocklist' idea, this led to my post earlier as Joe had issues with DDoS on the addresses he had listed in the root nameservers - which I figure is the weakest link all round... Someone has suggested 'anycasting' what do people (particually you Paul) think of using anycasting for a DNSbl? (- AS112 anyone?) I think it may work well... however I am a novice in terms of BGP... As far as I can tell it involves getting a portable address block (somone suggested anything less than a /24 would get filtered) and announcing it in various locations around the Net with local servers behind each of those announcements.... is this fundamentally correct? Assuming I am right in my current understanding, I am about to start looking at the proceedure to get an ASN and then I'll be looking for some portable IP space if the consensus and thoughts are this will work. I am thinking along the lines of talking with the other large DNSbls (particually Easynet (wirehub) and DSBL) about setting up a set of combined DNSbl servers all anycast'd. This after all will bring an DDoS machines to the attention of the local networks they are attacking .... ;-) Thoughts, comments, flames...? Thanks for all the offers of support and help, I will get back to everyone in detail as soon as I get chance. Yours Mat
On woensdag, aug 27, 2003, at 13:54 Europe/Amsterdam, Matthew Sullivan wrote:
Someone has suggested 'anycasting' what do people (particually you Paul) think of using anycasting for a DNSbl? (- AS112 anyone?) I think it may work well... however I am a novice in terms of BGP... As far as I can tell it involves getting a portable address block (somone suggested anything less than a /24 would get filtered) and announcing it in various locations around the Net with local servers behind each of those announcements.... is this fundamentally correct?
I wouldn't recommend this. If you have two DNS servers on different addresses, everyone can talk to #2 if #1 doesn't answer. If you anycast them, everyone only gets to talk to one, and if that one has problems, too bad, nothing to be done about that except wait until someone fixes the problem or changes the BGP announcement. Also, the built-in DNS RTT load balancing is much more sophisticated than BGP shortest path selection. I also have serious doubts about the wisdom of having the root servers anycast for similar reasons but in this case the only alternative is not increasing the number of servers as it's impossible to list the new servers under an IP address of their own. If the number of requests on your servers is the problem and not bandwidth, you could install filters that only allow requests for known users of the service. This means the attackers must first guess and then spoof an address belonging to a registered user, which should take much of the fun out of it. This sounds like a lot of work but you'd have to do something like it anyway when you want to become a paid service.
On Wed, 27 Aug 2003, Iljitsch van Beijnum wrote:
I wouldn't recommend this. If you have two DNS servers on different addresses, everyone can talk to #2 if #1 doesn't answer.
I noticed that many Windoze mail servers don't bother to check the second server if the primary's dead. --vadim
participants (8)
-
George William Herbert -
Iljitsch van Beijnum -
jlewis＠lewis.org -
Margie -
Matthew Sullivan -
Michael K. Smith -
Paul Vixie -
Vadim Antonov