I often (but not always) get the following error when running MPI jobs after switching wifi hosts.
Fatal error in MPI_Init: Other MPI error, error stack:
MPIR_Init_thread(498)..............:
MPID_Init(187).....................: channel initialization failed
MPIDI_CH3_Init(89).................:
MPID_nem_init(320).................:
MPID_nem_tcp_init(171).............:
MPID_nem_tcp_get_business_card(418):
MPID_nem_tcp_init(377).............: gethostbyname failed, MacBook-Pro.local (errno 1)
Everything works fine in the coffee shop, and then when I come home, I get the above error. Nothing else has changed.
I've checked the /etc/hosts and /private/etc/hosts files, and they look okay -
##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
##
127.0.0.1 localhost
255.255.255.255 broadcasthost
I can ping localhost, so the problem isn't exactly that localhost isn't resolved.
Rebooting always fixes the problem, but is there something simple I can do to "reset" my system so that it recognizes local host?
I don't have access to the details of the MPI initialization routines in the code I am running and am not making any explicit calls to gethostname.
I am using MPICH 3.1.4 (built Feb, 2015) and am running OSX 10.10.3
The answer is very simple - here is what seems to work.
I edited the file /etc/hosts (or /private/etc/hosts, in OSX) and added the line
127.0.0.1 macbook-pro.local
so now my hosts files looks like :
##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
##
127.0.0.1 localhost
255.255.255.255 broadcasthost
127.0.0.1 macbook-pro.local
We were facing this issue intermittently on our CI server. It seems that setting the environment variable MPICH_INTERFACE_HOSTNAME to localhost helped.
Related
My mac won't connect to localhost, I've tried with Safari and Mozilla, so it's not the browser, I tried other solutions I found on the internet, I ping 127.0.0.1 and it works correctly, if I run dscacheutil -q host -a name localhost I get the following:
name: localhost
ipv6_address: ::1
name: localhost
ip_address: 127.0.0.1
If I run apachectl configtest I get Syntax OK.
I've also read that my /etc/hosts might have been corrupted, this is how it looks like:
##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
##
127.0.0.1 localhost
255.255.255.255 broadcasthost
::1 localhost
# Added by Docker Desktop
# To allow the same kube context to work on the host and the container:
127.0.0.1 kubernetes.docker.internal
# End of section
I have no idea what else to try
EDIT: I'm trying to run an application (Hortonworks Sandbox) from a virtual machine (VirtualBox) in mac, I was advised to try port forwarding but this is what I see when I check the port forwarding in VirtualBox, seems like everything is in order:
I also tried to run Vagrant from VirtualBox and Mac couldn't connect to the localhost server when needed
I am trying to follow the getting started guide at https://docs.cypress.io/guides/getting-started/installing-cypress.html#System-requirements and when I run the following command
npx cypress open
it opens a popup and lists all the example specs. For now I am just running the example specs but this where I am facing the issue. It opens a browser but the page is just blank and I see the following error in the console,
Websocket connection to
'ws://localhost:62083/__socket.io/?EIO=3&transport=websocket' failed:
Connection closed before receiving a handshake response
I tested the same app in another machine and it works but its not working on my machine. Is there something that is causing the issue. My laptop is an office laptop is behind proxy. I checked the cypress proxy setting and I see that the proxy is correctly configured.
I had the same issue on my mac and this comment from filiphric solved the problem: https://github.com/cypress-io/cypress/issues/1239#issuecomment-419657694
open terminal, type: sudo nano /etc/hosts
if nothing is present, input defaults:
##
##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
##
127.0.0.1 localhost
255.255.255.255 broadcasthost
::1 localhost
fe80::1%lo0 localhost
save and close. (ctrl + X then y then enter)
reopen cypress and all should work normally
Hope it can help you too!
I ran into the problem, that localhost redirects to a specific domain instead of 127.0.0.1.
My configuration is a local apache/mysql/php installation on MacOS Mojave using vhosts for different projects that are configured in hosts to redirect properly.
When I enter 127.0.0.1 in any browser, I get to my overview page lying in the www root. The same should happen, when I enter localhost in the browser, but instead it redirects to a domain of a project I was working on in the past. It happens also without network connection, so the configuration is on this machine.
My /etc/hosts file:
##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
##
127.0.0.1 localhost project1.local project2.local
255.255.255.255 broadcasthost
::1 localhost
fe80::1%lo0 localhost
The first line seems to be ignored and localhost doesn't resolve to 127.0.0.1.
I only have two vhost configurations plus default configuration with no wrong redirection and also the httpd.conf lookes fine. I searched the whole machine with grep -lr "redirectiondomain.com" * without results. I tried with apache switched off with the same result and looked up the MacOS network settings but I can't find anything related to the wrong redirection neither any other solution on stackoverflow or google that solves my issue. Has anybody a clue how the wrong redirection of localhost could be set somewhere else?
Edit: My hostname in MacOS is set. I tried localhost without port, with :80 and :8080
Whenever I start Tomcat, and open http://localhost:8080 I get the following error.
Safari can’t open the page “localhost:8080” because Safari can’t connect to the server “localhost”.
It used to work before today. All I did earlier today was block some websites using the host files, but I restored them back again, and now it looks like this.
#
##
# Host Database
#
#
# localhost is used to configure the lookback interface
# when the system is booting. Do not change this entry.
##
127.0.0.1 localhost
255.255.255.255 broadcasthost
::1 localhost
fe80::1%lo0 localhost
If I start and stop the server using Eclipse, it works. But localhost can’t connect to server using Safari or Google Chrome either..
I know there are a lot of similar questions, but none of them seemed to help.
Thanks a lot in advance!
I am running a RoR app on my local. I have some translations in my hosts file.
127.0.0.1 localhost
127.0.0.1 example.dev
127.0.0.1 www.example.dev
127.0.0.1 api.example.dev
They were working fine, until I updated my OS to 10.11.4. If I send ping request to www.example.dev, it seems to work fine. The IP it translates to is 127.0.0.1.
But when I visit www.example.dev in my web browser, it seems to ignore hosts file and ping DNS server for IP.
I am not sure how, but going to localhost in browser does translate to 127.0.0.1.
Dont know why but ive disabled my lookback adapter and ipv6 and now its working.
so in your host file disable these two items
# ::1 localhost
# fe80::1%lo0 localhost
Some fubar osx bug... I miss steve....
I came across this while searching for an answer to a similar problem and wanted to post my findings for anyone else in the same position.
As a team of three, we found that edits to my /etc/hosts file appeared to work, while editing the other two's host files seemingly did not. Upon further digging, we realized I was on OS X 10.10, while they were on newer versions.
We found, after trying about a million things, that additions to the hosts file in 10.11 and up apparently could not have more than one space between the IP and the domain, for example:
DID NOT WORK:
1.2.3.4 some.site.com
DID WORK:
1.2.3.4 some.site.com
After making this change, we immediately started seeing expected results without any cache clears, reboots, or otherwise.
The host you are overriding is resolving via IPV6. ::1 is the loopback address for IPV6 which is analogous to 127.0.0.1 in IPV4. Add the following entries as the last lines in your /etc/hosts file.
::1 localhost::1 www.example.dev