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Re: [Wlug] ssh woes followup

by Karl Hiramoto

what is the output of: cat /proc/sys/fs/file-nr the format is documented in <linux-source>/Documentation/filesystems/proc.txt On Fri, 29 Aug 2003, Karl Hiramoto wrote: > > Is there anything showing up in /var/log/messages ? > > On Fri, 29 Aug 2003 mhughes(a)wpidalamar.com wrote: > > > > > > > On Thu, 28 Aug 2003, Matt Higgins wrote: > > > > > > It is possible you are running out of file descriptors. Running out of fd's > > > shows up in strange ways! Did you bounce ssh on both sides of the tunnel. More > > > importantly on the receiving end ;). Try running ssh/scp with the -v flag set, > > > it may give you some good info. Run tcpdump .. are you dropping a ton of > > > packets? Do a simple ping to see if there is packet loss? Do a ifconfig are > > > there a ton of errs on the interface you are leaving on/ receiving from? > > > > > > If you see you are dropping a lot of packets but there are no interface err's > > > you can encourage the person that admins the VPN to check it out! > > > > > > > > > Matt > > > > > > > > > _______________________________________________ > > > Wlug mailing list > > > Wlug(a)mail.wlug.org > > > http://mail.wlug.org/mailman/listinfo/wlug > > > > > > > > > > > > > I tried bouncing ssh at both ends... even doing a kill of all the > > processes of both ssh and sshd at both ends. > > > > scp -v doesn't show any weirdness. > > > > Ping works well, there's not an abnormal amount of errors in ifconfig. > > > > Is the open file limit system wide, or user specific? Mine's set for > > 4096, I've tried killing off a bunch of rarely used services on both > > machines to get the file count down. > > > > Now... this morning I'm noticing I can scp from the remote machine to the > > local machine, but not the other way around. In other words, from the > > remote machine, this works: > > scp qaddonline hughesm(a)10.1.0.19: > > But copying it back doesn't. > > scp hughesm@10.1.0.19:qaddonline . > > > > (qaddonline is about a 2 meg file) > > > > Also... from the local machine, iI can pull things down > > scp hughesm@10.21.2.184:qaddonline . > > but not push things up > > scp qaddonline hughesm(a)10.21.2.184: > > > > This didn't work last night. > > > > I can also now send small files (I tried one less than 1k) fine. > > > > I'd also like to add there's 2 machines in the remote facility that both > > have identical behavior. So I'm thinking it's either the link or my local > > machine. > > > > I'm no tcpdump expert, and both these machines have a good deal of > > traffic. What's an easy way to see if packets are getting dropped? > > (yeah, I suck at tcpdump filters). > > > > Any other ideas on things to look for? > > -Marc > > > > > > _______________________________________________ > > Wlug mailing list > > Wlug(a)mail.wlug.org > > http://mail.wlug.org/mailman/listinfo/wlug > > > > -- ¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø Karl Hiramoto <karl(a)hiramoto.org> Work: 978-425-2090 ext 25 Cell: 508-517-4819 http://karl.hiramoto.org/ AOL IM ID = KarlH420 Yahoo_IM = karl_hiramoto ¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø To iterate is human, to recurse, divine. -- Robert Heller

Aug. 29, 2003

Re: [Wlug] ssh woes followup

by Karl Hiramoto

Is there anything showing up in /var/log/messages ? On Fri, 29 Aug 2003 mhughes(a)wpidalamar.com wrote: > > > On Thu, 28 Aug 2003, Matt Higgins wrote: > > > > It is possible you are running out of file descriptors. Running out of fd's > > shows up in strange ways! Did you bounce ssh on both sides of the tunnel. More > > importantly on the receiving end ;). Try running ssh/scp with the -v flag set, > > it may give you some good info. Run tcpdump .. are you dropping a ton of > > packets? Do a simple ping to see if there is packet loss? Do a ifconfig are > > there a ton of errs on the interface you are leaving on/ receiving from? > > > > If you see you are dropping a lot of packets but there are no interface err's > > you can encourage the person that admins the VPN to check it out! > > > > > > Matt > > > > > > _______________________________________________ > > Wlug mailing list > > Wlug(a)mail.wlug.org > > http://mail.wlug.org/mailman/listinfo/wlug > > > > > > > > I tried bouncing ssh at both ends... even doing a kill of all the > processes of both ssh and sshd at both ends. > > scp -v doesn't show any weirdness. > > Ping works well, there's not an abnormal amount of errors in ifconfig. > > Is the open file limit system wide, or user specific? Mine's set for > 4096, I've tried killing off a bunch of rarely used services on both > machines to get the file count down. > > Now... this morning I'm noticing I can scp from the remote machine to the > local machine, but not the other way around. In other words, from the > remote machine, this works: > scp qaddonline hughesm(a)10.1.0.19: > But copying it back doesn't. > scp hughesm@10.1.0.19:qaddonline . > > (qaddonline is about a 2 meg file) > > Also... from the local machine, iI can pull things down > scp hughesm@10.21.2.184:qaddonline . > but not push things up > scp qaddonline hughesm(a)10.21.2.184: > > This didn't work last night. > > I can also now send small files (I tried one less than 1k) fine. > > I'd also like to add there's 2 machines in the remote facility that both > have identical behavior. So I'm thinking it's either the link or my local > machine. > > I'm no tcpdump expert, and both these machines have a good deal of > traffic. What's an easy way to see if packets are getting dropped? > (yeah, I suck at tcpdump filters). > > Any other ideas on things to look for? > -Marc > > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > -- ¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø Karl Hiramoto <karl(a)hiramoto.org> Work: 978-425-2090 ext 25 Cell: 508-517-4819 http://karl.hiramoto.org/ AOL IM ID = KarlH420 Yahoo_IM = karl_hiramoto ¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø To iterate is human, to recurse, divine. -- Robert Heller

Aug. 29, 2003

Re: [Wlug] SSH doesn't like me.

by Gary Hanley

I had a similar problem at the office and it turned out to be a NIC that was reconfigured by someone.....somehow. I think it was set to half-duplex instead of full-duplex...or vise-versa. -- Gary On Thu, 28 Aug 2003 mhughes(a)wpidalamar.com wrote: > So I use rsync over ssh to copy up & down a lot of stuff nighlty between > servers. On Monday, it all went to crap and won't work anymore. The > rsync's just never finish. > > So I went ahead and tried to use scp to copy the stuff over manually.. and > now IT times out! It transfers about 168KB, then goes "STALLED". If I > have a file smaller than 168kb, it goes through the entire progress-meter, > but then scp hangs, never returns, and the file it supposedly copied up is > 0 length. > > No special parameters on the scp or anything, but I do get a weird > message: > > scp * hughesm@apollo.tomsnyder.com:/data/www/htdocs/playtesting/ > > In my syslog... I don't anything weird. > Aug 28 15:17:17 apollo sshd[9774]: Could not reverse map address > 10.1.0.249. > Aug 28 15:17:17 apollo sshd[9774]: Accepted rsa for hughesm from > 10.1.0.249 port 637 > Aug 28 15:17:17 apollo PAM_unix[9776]: (sshd) session opened for user > hughesm by (uid=500) > > I have ssh keys set up for passwordless login. > > I've restarted ssh (making sure ALL the sshd processes died), I've killed > off all the rsync processes. Interactive ssh seems to work fine. > > Production machines that can't really be rebooted. > > Any Ideas? > -Marc > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > >

Aug. 29, 2003

Re: [Wlug] ssh woes followup

by mhughes＠wpidalamar.com

On Thu, 28 Aug 2003, Matt Higgins wrote: > > It is possible you are running out of file descriptors. Running out of fd's > shows up in strange ways! Did you bounce ssh on both sides of the tunnel. More > importantly on the receiving end ;). Try running ssh/scp with the -v flag set, > it may give you some good info. Run tcpdump .. are you dropping a ton of > packets? Do a simple ping to see if there is packet loss? Do a ifconfig are > there a ton of errs on the interface you are leaving on/ receiving from? > > If you see you are dropping a lot of packets but there are no interface err's > you can encourage the person that admins the VPN to check it out! > > > Matt > > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > > > I tried bouncing ssh at both ends... even doing a kill of all the processes of both ssh and sshd at both ends. scp -v doesn't show any weirdness. Ping works well, there's not an abnormal amount of errors in ifconfig. Is the open file limit system wide, or user specific? Mine's set for 4096, I've tried killing off a bunch of rarely used services on both machines to get the file count down. Now... this morning I'm noticing I can scp from the remote machine to the local machine, but not the other way around. In other words, from the remote machine, this works: scp qaddonline hughesm(a)10.1.0.19: But copying it back doesn't. scp hughesm@10.1.0.19:qaddonline . (qaddonline is about a 2 meg file) Also... from the local machine, iI can pull things down scp hughesm@10.21.2.184:qaddonline . but not push things up scp qaddonline hughesm(a)10.21.2.184: This didn't work last night. I can also now send small files (I tried one less than 1k) fine. I'd also like to add there's 2 machines in the remote facility that both have identical behavior. So I'm thinking it's either the link or my local machine. I'm no tcpdump expert, and both these machines have a good deal of traffic. What's an easy way to see if packets are getting dropped? (yeah, I suck at tcpdump filters). Any other ideas on things to look for? -Marc

Aug. 29, 2003

Next meeting: topic?

by Andy Stewart

HI everybody, Since our next meeting will be the first meeting of the academic year with the WPI students, do people think that a "What is Linux" meeting, geared for neophytes, would be a good meeting topic? We could also assess the interest level in having a campus install fest in the library (perhaps in October), as we've done in the past. Your thoughts? Thanks, Andy -- Andy Stewart, Founder Worcester Linux Users' Group Worcester, MA USA http://www.wlug.org

Aug. 29, 2003

Re: [Wlug] ssh woes followup

by Matt Higgins

Quoting Karl Hiramoto <karl(a)zoop.org>: > >From both machines can you scp into them? are they having problems > receiving large amounts of data? can you scp or ftp data into them? > > > Check for any open large files. Logs getting full? Possible you're > reaching your open files limit. Recently i had a squid proxy machine > stop working. There was plenty of free disk space and inodes. but > the kernel had a limit on how many open files there could be. I > deleted a 2G log file i hadn't setup with logrotate and the problem > was fixed. > > what does ulimit -a output? > cat /proc/sys/fs/file-max > try adding: > "ulmit -n 4095" at the begining your rsync script. > > try using the "find" command to find files larger than 1G see if they > are causing problems. anything at the 2G limit could be an issue. > depending on what filesystem you are using. > > > On Thu, 28 Aug 2003 mhughes(a)wpidalamar.com wrote: > > > > > Also... From both machines, I can scp to an external machine. These 2 > > boxes I'm having problems with are on opposite sides of an intracompany > > vpn. Could I be having problems with the vpn? The VPN is a big-expensive > > > end to end hardware solution that I don't get to play with. If it were > > that, any ideas on how I could prove that to corporate IT? > > > > Please note... it's possible that the vpn has nothing to do with the > > problem. > > > > -Marc > > > > _______________________________________________ > > Wlug mailing list > > Wlug(a)mail.wlug.org > > http://mail.wlug.org/mailman/listinfo/wlug > > > > -- > > ¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø > Karl Hiramoto <karl(a)hiramoto.org> > Work: 978-425-2090 ext 25 > Cell: 508-517-4819 > http://karl.hiramoto.org/ > AOL IM ID = KarlH420 Yahoo_IM = karl_hiramoto > ¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø > > QOTD: > "I used to jog, but the ice kept bouncing out of my glass." > > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > > The file-max param is for the max number of file descriptors not file size, Further more deleting large files would not solve either problem (Unless your fs was actually full in which case you would have another set of problems) FD's are taken then freed all the time (open/close files open/close sockets etc..) which is why fd problems are intermittent and hard to track.I suspect your squid problem would be better solved by increasing you file-max param or editing limits.h next time you build you kernel. On server systems file-max should be set to (RAM-SIZE/4)*256 256 fd per 4 megs of ram. This is not a hard number but a good rule of thumb. To set this every time you boot edit /etc/sysctl.conf (on most systems) or add it to rc.local. It is possible you are running out of file descriptors. Running out of fd's shows up in strange ways! Did you bounce ssh on both sides of the tunnel. More importantly on the receiving end ;). Try running ssh/scp with the -v flag set, it may give you some good info. Run tcpdump .. are you dropping a ton of packets? Do a simple ping to see if there is packet loss? Do a ifconfig are there a ton of errs on the interface you are leaving on/ receiving from? If you see you are dropping a lot of packets but there are no interface err's you can encourage the person that admins the VPN to check it out! Matt

Aug. 28, 2003

Re: [Wlug] ssh woes followup

by Karl Hiramoto

Aug. 28, 2003

ssh woes followup

by mhughes＠wpidalamar.com

Also... From both machines, I can scp to an external machine. These 2 boxes I'm having problems with are on opposite sides of an intracompany vpn. Could I be having problems with the vpn? The VPN is a big-expensive end to end hardware solution that I don't get to play with. If it were that, any ideas on how I could prove that to corporate IT? Please note... it's possible that the vpn has nothing to do with the problem. -Marc

Aug. 28, 2003

Re: [Wlug] Query regarding email applications...

by mhughes＠wpidalamar.com

you only want to move email? or addresses and everything else? If it's only email the easiest thing to do is to set up an IMAP server. Then connect to the imap server from your "source" client, copy your messages to the server, log in to IMAP with your "destination" client and copy them down. *OR* ... just always use an imap server and don't store your email on the client. -Marc On Mon, 25 Aug 2003, Stephen C. Daukas wrote: > Hi all! > > I am currently using mozilla 1.3.1 and want to be able to move my email > to other applications. I'd like to be able to move it to Netscape, > Eudora, and yes, Outlook. The reason for this is to show my new > department head why folks using different operating systems, say Linux, > should be allowed to use different operating systems as well as > different email applications. His only concern is "email compatibility". > > Now, once upon a time, it was really easy to move the files between > Netscape and Eudora, for example. They both had simple files that > contained the information (e.g., Eudora used to use .toc of the index, > and .mbx for the actual email while Netscape use to use - well, I can't > remember, but is was a similar flat file arrangement). > > So, I took a quick look at Eudora 5.1, and it looks like the familiar > old setup. Mozilla 1.3.1 looks like it is using a database of some sort > (.sdb?) and Netscape 7.1 looks, well, different from what I remember! > In the good old days, I could figure this out in a few minutes and would > have replicated my email across all of these apps! the last time I did > this was about 3 years ago as a demonstration of the very same point. Sigh! > > So, I decided to see how the import capabilities look and, well, they > don't play well, as far as I can tell. Outlook and Eudora have no idea > about Mozilla, and it doesn't look like Netscape does either. > > The point to all this is the following question: > > I have a boss who is predisposed to setting up Linux for those in his > department who are interested (he might be as well). He wants to be > able to "import & export" between Outlook and whatever on whatever. Is > there a way to show him that he can have his cake and eat it too, either > by moving files, or by using more than one email application as an > intermediary (e.g., Mozilla -> Outlook Express -> Eudora)? > > Steve > > -- > Stephen C. Daukas - stephen(a)daukas.com - http://daukas.com/ > > > > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > > >

Aug. 28, 2003

SSH doesn't like me.

by mhughes＠wpidalamar.com

So I use rsync over ssh to copy up & down a lot of stuff nighlty between servers. On Monday, it all went to crap and won't work anymore. The rsync's just never finish. So I went ahead and tried to use scp to copy the stuff over manually.. and now IT times out! It transfers about 168KB, then goes "STALLED". If I have a file smaller than 168kb, it goes through the entire progress-meter, but then scp hangs, never returns, and the file it supposedly copied up is 0 length. No special parameters on the scp or anything, but I do get a weird message: scp * hughesm@apollo.tomsnyder.com:/data/www/htdocs/playtesting/ In my syslog... I don't anything weird. Aug 28 15:17:17 apollo sshd[9774]: Could not reverse map address 10.1.0.249. Aug 28 15:17:17 apollo sshd[9774]: Accepted rsa for hughesm from 10.1.0.249 port 637 Aug 28 15:17:17 apollo PAM_unix[9776]: (sshd) session opened for user hughesm by (uid=500) I have ssh keys set up for passwordless login. I've restarted ssh (making sure ALL the sshd processes died), I've killed off all the rsync processes. Interactive ssh seems to work fine. Production machines that can't really be rebooted. Any Ideas? -Marc

Aug. 28, 2003