deke@ee.rochester.edu (Dikran Kassabian) (10/12/89)
At my site I get mail destined for user "usenet". We run Cnews. Today I got
the following in mail from usenet to usenet:
/usr/lib/news/sys file has been sent to moocow.mcw.edu!brodie. Remain calm.
Under what circumstances can my sys file get requested by and sent to others?
For what purpose?
^Deke Kassabian, deke@ee.rochester.edu or ur-valhalla!deke
Univ of Rochester, Dept of EE, Rochester, NY 14627 (+1 716-275-3106)tale@pawl.rpi.edu (David C Lawrence) (10/12/89)
In <1989Oct11.211031.10051@ee.rochester.edu> deke@ee.rochester.edu
(Dikran Kassabian) writes:
Dikran> Under what circumstances can my sys file get requested by and
Dikran> sent to others? For what purpose?
brodie@moocow.mcw.edu requested the sys file of every site in the
world with a "sendsys" control message. Modern control messages are
identified by the Control: header line, though older format are
supported. Commands for control messages include "cancel msg-id",
"newgroup group [moderated]", "rmgroup group", "sendsys", "senduuname"
and "version". These messages get filed in the pseudo-group control.
Sendsys requests that each site receiving the message send its sysfile
to the requestion. This can be used to check on network connexions
and see the scope of a distribution (though senduuname and version
will give you a lot fewer bytes in your mailbox). A couple of weeks
ago I sent out a Distribution: capdist sendsys to check on local
connectivity and found a leak out to another site that I don't believe
really wants capdist.
Basically, just do what it says. Remain calm. Unless of course you
make lots of nasty comments about other admins in your sys file, in
which case you can panic.
Dave
--
(setq mail '("tale@pawl.rpi.edu" "tale@itsgw.rpi.edu" "tale@rpitsmts.bitnet"))chuq@Apple.COM (Chuq Von Rospach) (10/12/89)
>brodie@moocow.mcw.edu requested the sys file of every site in the >world with a "sendsys" control message. Gads. I hope he has a *large* disk in /usr/spool/mail. -- Chuq Von Rospach <+> Editor,OtherRealms <+> Member SFWA/ASFA chuq@apple.com <+> CI$: 73317,635 <+> [This is myself speaking] Future home of the San Jose Photons! I was a Kings fan before it was politically correct. NHL to San Jose!
coolidge@brutus.cs.uiuc.edu (John Coolidge) (10/12/89)
chuq@Apple.COM (Chuq Von Rospach) writes: >>brodie@moocow.mcw.edu requested the sys file of every site in the >>world with a "sendsys" control message. >Gads. I hope he has a *large* disk in /usr/spool/mail. Actually, he's on a VMS machine, so the mail goes directly into his mail folder analogue. He _might_ be safe if on a quota'd disk, since overquota mail might just be bounced --- unless mail has exquota privs. In that case, it's hello full user disk, and probably bye bye any mail (since the only reasonable recovery is mass delete). This brings up a point: if you just want to check connectivity, the 'version' control is almost certainly a better option. Or 'senduuname'. 'sendsys' should be reserved for cases when you _really_ want a sys file (for debugging a feed, for instance), and should be carefully checked for the right Distributions: and Newsgroup: headers before releasing it into the world. 'version' and 'senduuname' both give you just one line of output (plus the obligatory massive headers). 'sendsys' gives you lots of lines for each site... --John -------------------------------------------------------------------------- John L. Coolidge Internet:coolidge@cs.uiuc.edu UUCP:uiucdcs!coolidge Of course I don't speak for the U of I (or anyone else except myself) Copyright 1989 John L. Coolidge. Copying allowed if (and only if) attributed. You may redistribute this article if and only if your recipients may as well.
jim@eda.com (Jim Budler) (10/12/89)
deke@ee.rochester.edu (Dikran Kassabian) writes: } Under what circumstances can my sys file get requested by and sent to others? } For what purpose? } ^Deke Kassabian, deke@ee.rochester.edu or ur-valhalla!deke } Univ of Rochester, Dept of EE, Rochester, NY 14627 (+1 716-275-3106) Under most any circumstances. A person posts a sendsys control message. For what purpose? Usually to check out neighbors sys files to verify your connection. Usually gets out further than that though. The poor sucker who does it improperly gets *lots* of mail. Nothing to worry about, unless you really truly don't want people to know about your news connections for some reason. However, given that you are running cnews, if you chose to be paranoid about it, you can edit the script /usr/lib/newsbin/ctl/sendsys like so: *** /tmp/,RCSt1a09865 Wed Oct 11 16:47:42 1989 --- sendsys Wed Oct 11 16:47:31 1989 *************** *** 9,16 **** SENDER="`newsreply`" (echo "Subject: response from `newshostname` to your sendsys"; echo ""; ! case "$1" in ! "") cat $NEWSCTL/sys ;; ! *) awk -f $NEWSBIN/relay/canonsys.awk $NEWSCTL/sys | egrep "^$1:" ;; ! esac ) | mail "$SENDER" ! echo "$NEWSCTL/sys file has been sent to $SENDER. Remain calm." | mail $NEWSMASTER --- 9,13 ---- SENDER="`newsreply`" (echo "Subject: response from `newshostname` to your sendsys"; echo ""; ! echo "Sorry. We don't do sendsys.") | mail "$SENDER" ! echo "$NEWSCTL/sys file has been requested by $SENDER. Remain calm." | mail $NEWSMASTER -- Jim Budler jim@eda.com ...!{decwrl,uunet}!eda!jim compuserve: 72415,1200 applelink: D4619 voice: +1 408 986-9585 fax: +1 408 748-1032
brodie@fps.mcw.edu (10/12/89)
Actually, I was not aware of "version" and "uuname" control messages. Because I'm running a VMS implementation of news, I don't have all the documentation that normally gets distributed with unix-like news. As far as my disk capacity, I don't have quotas set, and have virtually a whole disk to myself. As far as the distribution goes, I did indeed make a mistake in that I *intended* it to be usa-based only. Oh well :-( Why do I feel like Greg Morris? -k
hoyt@bessie.nac.dec.com (Kurt Hoyt) (10/13/89)
>>brodie@moocow.mcw.edu requested the sys file of every site in the >>world with a "sendsys" control message. I have received 35 of these -- no make that 36: another just arrived -- is there anyway to shut this down at my end without turning off news? Kurt Hoyt Digital Equipment Corporation hoyt@decatl.dec.com "Excuse me, doctor, I'm receiving several distress calls."
coolidge@brutus.cs.uiuc.edu (John Coolidge) (10/13/89)
brodie@fps.mcw.edu writes: >Actually, I was not aware of "version" and "uuname" control messages. >Because I'm running a VMS implementation of news, I don't have all >the documentation that normally gets distributed with unix-like news. I have a feeling that a lot of administrators don't know about 'version' or 'senduuname'. I found out about them more-or-less by accident (docs? I don't need no stinkin' docs!). The relevant RFCs (850 and 1036) are very useful references for this sort of thing. >As far as my disk capacity, I don't have quotas set, and have virtually >a whole disk to myself. Probably a very good thing! >As far as the distribution goes, I did indeed make a mistake in that >I *intended* it to be usa-based only. Oh well :-( It's not the first time. The last time one of these went wild, there was a lot more noise heard than this time. I suspect that's because the return messages haven't jammed any sites up yet (hopefully they won't, but they'll probably take out one or two :-( ). --John -------------------------------------------------------------------------- John L. Coolidge Internet:coolidge@cs.uiuc.edu UUCP:uiucdcs!coolidge Of course I don't speak for the U of I (or anyone else except myself) Copyright 1989 John L. Coolidge. Copying allowed if (and only if) attributed. You may redistribute this article if and only if your recipients may as well.
mcb@ncis.tis.llnl.gov (Michael C. Berch) (10/13/89)
In <1989Oct11.235318.23465@brutus.cs.uiuc.edu> coolidge@cs.uiuc.edu writes: > chuq@Apple.COM (Chuq Von Rospach) writes: > >>brodie@moocow.mcw.edu requested the sys file of every site in the > >>world with a "sendsys" control message. > > >Gads. I hope he has a *large* disk in /usr/spool/mail. > > Actually, he's on a VMS machine, so the mail goes directly into his mail > folder analogue. He _might_ be safe if on a quota'd disk, since overquota > mail might just be bounced --- unless mail has exquota privs. In that > case, it's hello full user disk, and probably bye bye any mail (since > the only reasonable recovery is mass delete). Huh? Am I missing something? According to the newsstats posting from uunet last week, there were about 5,100 sites posting news. The arbitron stats estimate a total of about 12,000 sites. That's an upper bound. I'm willing to wager that no more than 7,500 sites are able or willing to respond to a sendsys message. I have no clue as to the average size of a sys file, but ours is 2K bytes and is horrendously verbose, with contact info for every feed we've had in the last couple of years. I constructed a couple of "normal" sys files, and they seemed to be about 800 bytes -- let's round up to 1K. Thus, 7500 * 1024 = 7,680,000 ~= 7.7 MB. I'd say for all but the home systems or PCs, an extra 7.7MB of mail over a few days ain't going to fill up too many disks. At most places I'm familiar with it probably wouldn't be *noticed*, disk space-wise, though I'm sure the size of the mailer log might attract attention. -- Michael C. Berch mcb@tis.llnl.gov / uunet!tis.llnl.gov!mcb
bdb@becker.UUCP (Bruce Becker) (10/13/89)
In article <3194.25347675@fps.mcw.edu> brodie@fps.mcw.edu writes: |[...] |As far as the distribution goes, I did indeed make a mistake in that |I *intended* it to be usa-based only. Oh well :-( Hey! How about us Canadians! Use "Distribution: na" instead, pleez! Thanx, -- __ Bruce Becker Toronto, Ont. w \../ Internet: bdb@becker.UUCP, bruce@gpu.utcs.toronto.edu `/ /-e BitNet: BECKER@HUMBER.BITNET _/ \_ Beware the Fandom of the Oprah - P. Donahue
coolidge@brutus.cs.uiuc.edu (John Coolidge) (10/13/89)
mcb@ncis.tis.llnl.gov (Michael C. Berch) writes: >In <1989Oct11.235318.23465@brutus.cs.uiuc.edu> coolidge@cs.uiuc.edu writes: >> chuq@Apple.COM (Chuq Von Rospach) writes: >> >Gads. I hope he has a *large* disk in /usr/spool/mail. >> >> Actually, he's on a VMS machine, so the mail goes directly into his mail >> folder analogue. He _might_ be safe if on a quota'd disk, since overquota >> mail might just be bounced --- unless mail has exquota privs. In that >> case, it's hello full user disk, and probably bye bye any mail (since >> the only reasonable recovery is mass delete). >Huh? Am I missing something? According to the newsstats posting >from uunet last week, there were about 5,100 sites posting news. >The arbitron stats estimate a total of about 12,000 sites. That's an >upper bound. I'm willing to wager that no more than 7,500 sites are >able or willing to respond to a sendsys message. I have no clue as to >the average size of a sys file, but ours is 2K bytes and is >horrendously verbose, with contact info for every feed we've had in >the last couple of years. I constructed a couple of "normal" sys >files, and they seemed to be about 800 bytes -- let's round up to 1K. >Thus, 7500 * 1024 = 7,680,000 ~= 7.7 MB. I'd say for all but the >home systems or PCs, an extra 7.7MB of mail over a few days ain't >going to fill up too many disks. At most places I'm familiar with it >probably wouldn't be *noticed*, disk space-wise, though I'm sure the >size of the mailer log might attract attention. An extra 7.7MB of mail would blow our mail partition totally out of the water (of course, that's because it's way too small, but that's beside the point; it does happen). I have a feeling that most of the 9000ish sites in the comp.mail.maps list (vaguely remembered number, which is I think fairly accurate) will respond to a sendsys. I'd guess the number of responses to be at least 8000. Of course, what would be more valuable would some stats on what this sendsys actually produced... (of course, that confuses the issue with facts :-) ). But more importantly, 1024 bytes is _way_ too small a response pattern. Our sys file is around 4K. I've got the sys files of several of my connections on file, and the smallest was 3k, with the largest at 14K. Granted that I talk to large sites (I've got 12 connections, and my largest connection has 40), there are still a fair number of sites with five-ten connections around. 1K won't handle that many, not if anywhere near a broad range of groups are carried, or if any special batch files, etc., are specified. And all this is still ignoring all of the mail headers. For an average site, internet-internet transmission will entail around 400-800 bytes of mail headers. Once you go off the internet and into uucp, these group rapidly (more Received: headers, which are the big space user). I've seen 10K or larger mail headers, although these are rare. Considering that moocow is one hop off the internet (I think), and that most of the >8000 responders will be off the internet and not within short uucp range of moocow, mail headers alone will probably average in the 1K range. I'd guess that 2.5K*8000, or 20M, is a closer ballpark figure. It could still be short. 20M would put a serious crimp on many people's mail spool areas, I think. It would certainly mess us up if we were just carrying it for transmission, and it would totally overflow our mail disk if someone here was getting it. Again, I'd love some real numbers from moocow when all this settles down (average file size, number of sys files, etc.) And all of this ignores all of the letters of protest that could arise when sites find they're moving multiple megabytes of sys files around all headed for one site. (And, of course, the added news volume from discussing the added volume :-) ). And the poor link to moocow! This sort of volume will probably double the load on that link for a few days. --John -------------------------------------------------------------------------- John L. Coolidge Internet:coolidge@cs.uiuc.edu UUCP:uiucdcs!coolidge Of course I don't speak for the U of I (or anyone else except myself) Copyright 1989 John L. Coolidge. Copying allowed if (and only if) attributed. You may redistribute this article if and only if your recipients may as well.
asp@uunet.UU.NET (Andrew Partan) (10/13/89)
In article <1989Oct13.125402.17356@brutus.cs.uiuc.edu>, coolidge@brutus.cs.uiuc.edu (John Coolidge) writes: > Our sys file is around 4K. I've got the sys files of several of my > connections on file, and the smallest was 3k, with the largest at 14K. uunet's sys file: 176 -rw-rw-r-- 1 news 166812 Oct 13 09:40 /usr/spool/news-lib/sys This is probably the largest -:). We are feeding 404 sites & counting. --asp@uunet.uu.net (Andrew Partan) ASN.1 Object Identifier: "{joint-iso-ccitt mhs(6) group(6) 157}"
tale@pawl.rpi.edu (David C Lawrence) (10/14/89)
Me> brodie@moocow.mcw.edu requested the sys file of every site in the
Me> world with a "sendsys" control message.
In <1239@decatl.dec.com> hoyt@bessie.nac.dec.com (Kurt Hoyt) writes:
Kurt> I have received 35 of these -- no make that 36: another just
Kurt> arrived -- is there anyway to shut this down at my end without
Kurt> turning off news?
I'm not quite sure I understand this. You've received 36 of the sys
files that were sent to moocow? You mean via UUCP in your spool area
or something? Or mailed to you?
This is one of those things that unfortunately does little good to
cancel after its been sent out; for example, a newgroup that has a day
to propagate is going to hit an awful lot of sites and cancelling the
newgroup posting won't be the same as an rmgroup -- what's done is
done. The same applies for sendsys; that request has probably hit
over 80% of the sites that will receive it, and a cancel isn't likely
to catch up to it before it hits the rest. Most of all, turning off
news at your site is probably completely irrelevant to the current
problem you are having.
Dave
--
(setq mail '("tale@pawl.rpi.edu" "tale@itsgw.rpi.edu" "tale@rpitsmts.bitnet"))tale@pawl.rpi.edu (David C Lawrence) (10/14/89)
In article <3194.25347675@fps.mcw.edu> brodie@fps.mcw.edu writes:
brodie> As far as the distribution goes, I did indeed make a mistake in that
brodie> I *intended* it to be usa-based only. Oh well :-(
In <926@becker.UUCP> bdb@becker.UUCP (Bruce Becker) replied:
Bruce> Hey! How about us Canadians! Use "Distribution: na" instead, pleez!
Why? It was, after all, his sendsys for his own purposes (though I
too am curious about the results). Should I have made my capdist
sendsys na instead, too?
Dave
--
(setq mail '("tale@pawl.rpi.edu" "tale@itsgw.rpi.edu" "tale@rpitsmts.bitnet"))davidc@vlsisj.VLSI.COM (David Chapman) (10/14/89)
In article <1989Oct11.235318.23465@brutus.cs.uiuc.edu> coolidge@cs.uiuc.edu writes: <chuq@Apple.COM (Chuq Von Rospach) writes: <>>brodie@moocow.mcw.edu requested the sys file of every site in the <>>world with a "sendsys" control message. < <>Gads. I hope he has a *large* disk in /usr/spool/mail. < <Actually, he's on a VMS machine, so the mail goes directly into his mail <folder analogue. He _might_ be safe if on a quota'd disk, since overquota <mail might just be bounced --- unless mail has exquota privs. In that <case, it's hello full user disk, and probably bye bye any mail (since <the only reasonable recovery is mass delete). I don't know about net mail bouncing, but at our site under DECnet (local) the message simply isn't sent when the recipient's quota is exceeded, so we don't have to worry about one user taking over the whole disk. I don't know if you can change mail's privileges under VMS, so I can't guarantee his safety on his system. :-) -- David Chapman {known world}!decwrl!vlsisj!fndry!davidc vlsisj!fndry!davidc@decwrl.dec.com
bdb@becker.UUCP (Bruce Becker) (10/15/89)
In article <1989Oct13.222824.1845@rpi.edu> tale@pawl.rpi.edu (David C Lawrence) writes: |In article <3194.25347675@fps.mcw.edu> brodie@fps.mcw.edu writes: |brodie> As far as the distribution goes, I did indeed make a mistake in that |brodie> I *intended* it to be usa-based only. Oh well :-( | |In <926@becker.UUCP> bdb@becker.UUCP (Bruce Becker) replied: |Bruce> Hey! How about us Canadians! Use "Distribution: na" instead, pleez! | |Why? It was, after all, his sendsys for his own purposes (though I |too am curious about the results). Should I have made my capdist |sendsys na instead, too? True. I released a generic knee-jerk type of response here. It doesn't quite apply in the current circumstance, as you point out. But it is a problem for Canadian (& others I presume) sites, so the request still remains in general... Cheers, -- __ Bruce Becker Toronto, Ont. w \../ Internet: bdb@becker.UUCP, bruce@gpu.utcs.toronto.edu `/ /-e BitNet: BECKER@HUMBER.BITNET _/ \_ Beware the Fandom of the Oprah - P. Donahue
lamy@ai.utoronto.ca (Jean-Francois Lamy) (10/15/89)
Not that using usa over na will restrict distribution much; there is a lot of permeability on that matter (i.e. many major canadian gateways let usa postings through, and vice-versa). I can't come up with an example where a distriution "usa" posting would be absolutely and totally irrelevant up here; even the opposite "can" postings leaking in the "usa" with 100% canadian concerns usually generate interest and follow-ups in the US. The cultures are close enough to allow this yet different enough to make it entertaining, and there is no economic or political incentive to keep the articles out... Jean-Francois Lamy lamy@ai.utoronto.ca, uunet!ai.utoronto.ca!lamy AI Group, Department of Computer Science, University of Toronto, Canada M5S 1A4
hoyt@bessie.nac.dec.com (Kurt Hoyt) (10/16/89)
>Kurt> I have received 35 of these -- no make that 36: another just >Kurt> arrived -- is there anyway to shut this down at my end without >Kurt> turning off news? > >I'm not quite sure I understand this. You've received 36 of the sys >files that were sent to moocow? You mean via UUCP in your spool area No, I mean I received (in the end) around 45 sendsys control messages. In effect, moocow was sent (unsuccessfully, perhaps) 45 copies of my sys file. I wanted to know how to shutdown the sendsys request I was getting about once an hour. Some time on Friday, it stopped as silently as it began. Someone upstream must have done something.... Kurt Hoyt Digital Equipment Corporation hoyt@decatl.dec.com "Excuse me, doctor, I'm receiving several distress calls."
timcc@csv.viccol.edu.au (Tim Cook) (10/16/89)
In article <1989Oct11.235430.9923@eda.com>, jim@eda.com (Jim Budler) writes: > deke@ee.rochester.edu (Dikran Kassabian) writes: > > } Under what circumstances can my sys file get requested by and sent to others? > } For what purpose? > > ... > > Nothing to worry about, unless you really truly don't want people to > know about your news connections for some reason. > > However, given that you are running cnews, if you chose to be paranoid > about it, you can edit the script /usr/lib/newsbin/ctl/sendsys like so: [context diff to make Cnews paranoid deleted] Please note that modifiying Cnews to respond to a "sendsys" message with a message containing "Sorry, we don't do sendsys", will leave you with a non-standard news system. It is quite clearly stated in the Usenet news RFC that your sys file is regarded as public information, and therefore response to a "sendsys" message is regarded as the fulfillment of a right, and a mandatory part of the news software, designed to make the attainment of this right automatic. Also, should an effort be made to save all the sendsys responses being received by moocow? Surely they would be valuable. This could be known as the Great Usenet Census of 1989. -- Tim Cook Systems Administrator, Victoria College Computer Services parrot - n. An animal that has the ability to imitate man, but not the intelligence to refrain from doing so.
mcb@ncis.tis.llnl.gov (Michael C. Berch) (10/17/89)
[Re: what happens when you send out a global sendsys...] Thanks to John Coolidge for pointing out what I *did* miss in the original calculation: the size of the (expanding) mail header. That indeed could well add up to 1K by itself for a site a couple of hops off the Internet. I'd also accept the 8,000 sites vs. 7,500 sites estimate, though I think we're both speculating. But I really think that 1K is probably a good average sys file, since for every site that has 5-10 feeds there are several that have only 1 or 2, which might result in a 400-500 byte sys file (a hundred-char line for each feed, plus a line of contact info per site, plus a couple of lines of comments). So then we get 8,000 * 2048 = 16,384,000 ~= 16.4 MB You would hope that wouldn't blow too many mail spool disks, but perhaps so. The real squeeze, the one I forgot since we do not run UUCP on our news host, is the space required for pass-through mail. -- Michael C. Berch mcb@tis.llnl.gov / uunet!tis.llnl.gov!mcb
tale@pawl.rpi.edu (David C Lawrence) (10/17/89)
In article <1240@decatl.dec.com>, hoyt@bessie.nac.dec.com (Kurt Hoyt):
Kurt> No, I mean I received (in the end) around 45 sendsys
Kurt> control messages. In effect, moocow was sent (unsuccessfully,
Kurt> perhaps) 45 copies of my sys file. I wanted to know how to
Kurt> shutdown the sendsys request I was getting about once an hour.
Kurt> Some time on Friday, it stopped as silently as it began. Someone
Kurt> upstream must have done something....
Whoa. This is sure to add to the total bytes brodie@moocow got,
especially if other sites had this happen. Does anyone have any idea
why Kurt got 45 requests when we only got one? Kurt, did they all
have unique message-ids, or was it the same id? If the latter, and
your machine actually replied to each sendsys, how did that happen?
Dave
--
(setq mail '("tale@pawl.rpi.edu" "tale@itsgw.rpi.edu" "tale@rpitsmts.bitnet"))clarke@acheron.uucp (Ed Clarke/10240000) (10/17/89)
From article <547@ncis.tis.llnl.gov>, by mcb@ncis.tis.llnl.gov (Michael C. Berch): > [Re: what happens when you send out a global sendsys...] > 8,000 * 2048 = 16,384,000 ~= 16.4 MB > You would hope that wouldn't blow too many mail spool disks, but perhaps > so. The real squeeze, the one I forgot since we do not run UUCP Last year (December) I sent out a 'sendsys' with a NY distribution. Somehow it multiplied so that rochester.edu got 22 requests from me within a span of ten hours ... I still haven't figured out how it happened and have no intention of trying it again. So you only hope it's 16 meg - -- Ed Clarke acheron!clarke
richard@gryphon.COM (Richard Sexton) (10/18/89)
In article <1989Oct17.045700.11226@acheron.uucp> clarke@acheron.uucp (Ed Clarke/10240000) writes: >From article <547@ncis.tis.llnl.gov>, by mcb@ncis.tis.llnl.gov (Michael C. Berch): >> [Re: what happens when you send out a global sendsys...] >> 8,000 * 2048 = 16,384,000 ~= 16.4 MB >> You would hope that wouldn't blow too many mail spool disks, but perhaps >> so. The real squeeze, the one I forgot since we do not run UUCP > >Last year (December) I sent out a 'sendsys' with a NY distribution. >Somehow it multiplied so that rochester.edu got 22 requests from me >within a span of ten hours ... I still haven't figured out how it >happened and have no intention of trying it again. Perhaps there ought to be a limit in the software viz. how many times per day (hour?) it will respond to a sendsys. 100 sendsys requests per hour could get pretty annoying. -- Help wipe out BBQ lighter fluid in your lifetime richard@gryphon.COM decwrl!gryphon!richard gryphon!richard@elroy.jpl.NASA.GOV