I am bit confuse , my hosts file look like :
> 127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost localhost.localdomain
> localhost6 localhost6.localdomain6
> 127.0.0.1 autoreply.panel.mywebsite.com
> 127.0.0.1 myhostname
> 127.0.0.1 panel.mywebsite.com
why doesn't show the machine Ip address ?? Even so the website is working and the website is accessible from the web.
Anyone can please explain ?? Thank you
Think of /etc/hosts as a dns system override. You can specify hostnames by IP addresses in this file.
For example you could do the following:
echo "127.0.0.1 google.com" >> /etc/hosts
And proceed to ping google.com:
[jclark#jclark530 ~]$ ping -c1 google.com
PING google.com (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.028 ms
Your attached server IP address(es) will show by running /sbin/ifconfig
Related
Avahi/mDNS is running by default on recent versions of Raspian. Great. Very convenient to just ssh pi#mypi.local.
I am doing development on a Mac and operating a local network of headless Raspberry Pis. Up until now, I was able to use mDNS to access the Pis, and the Pis used mDNS to connect to each other.
Today, I shifted the RPis to a private local network by setting them up on a wireless router unconnected to the internet. Once I join the private network, I am still able to access them via mDNS:
% ssh pi#scheduler.local
Linux scheduler 5.10.63-v7l+ #1459 SMP Wed Oct 6 16:41:57 BST 2021 armv7l
Last login: Mon Aug 1 09:07:43 2022
pi#scheduler:~ $
and
wes#macbook % ssh pi#crossing.local
Linux crossing 5.10.17-v7l+ #1414 SMP Fri Apr 30 13:20:47 BST 2021 armv7l
Last login: Mon Aug 1 09:07:46 2022
pi#crossing:~ $
But when they try to access each other, I get some results I don't understand:
pi#scheduler:~ $ ping crossing.local
PING crossing.local (10.0.0.1) 56(84) bytes of data.
From 192.168.0.1 (192.168.0.1) icmp_seq=1 Destination Net Unreachable
From 192.168.0.1 (192.168.0.1) icmp_seq=2 Destination Net Unreachable
From 192.168.0.1 (192.168.0.1) icmp_seq=3 Destination Net Unreachable
From 192.168.0.1 (192.168.0.1) icmp_seq=4 Destination Net Unreachable
Here's what Avahi reports:
pi#scheduler:~ $ service avahi-daemon status
● avahi-daemon.service - Avahi mDNS/DNS-SD Stack
Loaded: loaded (/lib/systemd/system/avahi-daemon.service; enabled; vendor preset: enabled)
Active: active (running) since Mon 2022-08-01 09:07:37 PDT; 41min ago
Main PID: 388 (avahi-daemon)
Status: "avahi-daemon 0.7 starting up."
Tasks: 2 (limit: 1438)
CGroup: /system.slice/avahi-daemon.service
├─388 avahi-daemon: running [scheduler.local]
└─414 avahi-daemon: chroot helper
Aug 01 09:08:08 scheduler avahi-daemon[388]: Leaving mDNS multicast group on interface wlan0.IPv4 with address 169.
Aug 01 09:08:08 scheduler avahi-daemon[388]: Joining mDNS multicast group on interface wlan0.IPv4 with address 192.
Aug 01 09:48:29 scheduler avahi-daemon[388]: Files changed, reloading.
Aug 01 09:48:29 scheduler avahi-daemon[388]: No service file found in /etc/avahi/services.
Here's my hosts and hostname files:
pi#scheduler:~ $ cat /etc/hosts
127.0.0.1 localhost
::1 localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
127.0.1.1 scheduler
pi#scheduler:~ $ cat /etc/hostname
scheduler
What does avahi say about it? Let's see:
pi#brs-scheduler:~ $ avahi-resolve --name brs-crossing.local -4
brs-crossing.local 192.168.0.214
pi#brs-scheduler:~ $ ifconfig | grep "inet 192"
inet 192.168.0.109 netmask 255.255.255.0 broadcast 192.168.0.255
pi#brs-scheduler:~ $ ping brs-crossing.local
PING brs-crossing.local (10.0.0.1) 56(84) bytes of data.
From 192.168.0.1 (192.168.0.1) icmp_seq=1 Destination Net Unreachable
So for some reason, on this private network, mDNS is resolving correctly, but ping and ssh don't resolve properly?
What am I missing?
Unsurprisingly, since the pis worked fine on the local net and stopped working on a private net with a new router, it had to do with the configuration of the new router not mDNS.
mDNS was working fine:
pi#scheduler:~ $ avahi-resolve --name crossing.local -4
crossing.local 192.168.0.214
The new router on the private net had two operating modes "router" and "access point." In "router" mode, the router was pushing a DNS nameserver IP to clients which was somehow hosing ping and ssh and other services, despite mDNS working okay.
pi#scheduler:~ $ cat /etc/resolv.conf
# Generated by resolvconf
nameserver 192.168.0.1
Once the router was placed in "access point" mode, and DHCP was turned on manually, everything worked.
Obscure problem. Obscure solution.
I once did this configuration and it worked, but now on other machine is not working. I followed the instruction from sendgrid:
https://sendgrid.com/docs/for-developers/sending-email/sendmail/
But when i want to send an email it says:
sm-msp-queue[4439]: 07QAbRM1009651: to=smmsp, delay=01:20:57, xdelay=00:04:22, mailer=relay, pri=301852, relay=[127.0.0.1] [127.0.0.1], dsn=4.0.0, stat=Deferred: Connection timed out with [127.0.0.1]
I think that it should not be 127.0.0.1 but the smtp.sendgrid.net.
netstat -ntlp shows:
tcp 0 0 127.0.0.1:587 0.0.0.0:* LISTEN -
I also can telnet to smtp.sendgrid.net on port 587
I found the problem. There was an iptable rule that drops all loopback connection.
-A OUTPUT -o lo -j DROP
removed with
-D OUTPUT -o lo -j DROP
Make sure to save the new rules:
iptables-save > /etc/iptables/rules.v4
I want to invoke service in my kuberetes cluster, so I try to invoke servcie(the backend pod deployment by deplyment) like this:
curl http://soa-illidan-hub-service.dabai-fat.svc.cluster.local:11024
it tell me curl: (7) Failed to connect to soa-illidan-hub-service.dabai-fat.svc.cluster.local port 11024: Host is unreachable, and I am ping:
/ # ping soa-illidan-hub-service.dabai-fat.svc.cluster.local
PING soa-illidan-hub-service.dabai-fat.svc.cluster.local (10.254.42.62): 56 data bytes
64 bytes from 10.254.42.62: seq=0 ttl=64 time=0.051 ms
64 bytes from 10.254.42.62: seq=1 ttl=64 time=0.063 ms
64 bytes from 10.254.42.62: seq=2 ttl=64 time=0.057 ms
why the curl tell me host is unreachable? and. I could using endpoint ip to invoke servcie,should I using ip? using servcie ip is a good practice?
Try
wget -qO- http://soa-illidan-hub-service.dabai-fat.svc.cluster.local
or try directly to pod ip
wget -qO- POD_IP:PORT
I finnally find the reason, the pod's running node kube-proxy stopped. Try to start kube-proxy will fix this, in my centos 7.6 start like this:
systemctl start kube-proxy
I'm trying to configure Sendmail to listen on on 110 POP3 on a ec2 server. I need it for a newsletter app so that it can check for bounces. When I try to telnet in on port 110 I get a connection error.
root:/# telnet sub.domain.com 110
Trying 5?.??.?.?0...
telnet: Unable to connect to remote host: Connection refused
root:/# telnet sub.domain.com 25
Trying 5?.??.?.?0...
Connected to sub.domain.com.
Escape character is '^]'.
220 ip-172-31-54-114.ec2.internal ESMTP Sendmail 8.14.4/8.14.4/Debian-4.1ubuntu1; Wed, 30 Nov 2016 10:24:50 GMT; (No UCE/UBE) logging access from: [5?.??.?.?0](FORGED)-ec2-5?-??-?-?0.compute-1.amazonaws.com [5?.??.?.?0] (may be forged)
^]
telnet> quit
Connection closed.
When I lsof on port 25 I can see that it's working but not on 110.
root:/# lsof -n -i :25
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
sendmail- 4279 root 4u IPv4 2349285 0t0 TCP *:smtp (LISTEN)
root:/# lsof -n -i :110
root:/#
Do I need to edit the sendmail.mc file, previously I commented out the below lines so that smtp would listen to all IPs.
dnl DAEMON_OPTIONS(`Family=inet, Name=MTA-v4, Port=smtp, Addr=127.0.0.1')dnl
dnl DAEMON_OPTIONS(`Family=inet, Name=MSP-v4, Port=submission, M=Ea, Addr=127.0.0.1')dnl
I've searched the sendmail.cf & sendmail.mc for any references to pop3/port110 configuration but can't see anything.
Sendmail MTA acts like SMTP server. You need separate program/server to service POP3 protocol e.g. dovecot IMAP/POP server.
Sendmail-FAQ-4.19 : How do I configure sendmail for POP/IMAP/...?
When running: telnet localhost 25 on a box with postfix running (verified listening on port 25) the expected behavior is:
[user#box ~]$ telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
220 fqdn ESMTP
When I telnet to my box I get the following: (postfix 2.6.6)
[root#host postfix]# telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
^]
telnet> quit
Connection closed.
Postfix seems to be running
x]# netstat -plnt |grep :25
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN 44950/master
tfix]# ps -ef | grep post
root 44950 1 0 16:24 ? 00:00:00 /usr/libexec/postfix/master
I am trying to verify my postfix config and it does not even seem to be running on port 25 correctly. Any assistance/suggestions greatly appreciated. Thank you.
i hope you have set your
inet_interfaces = all in postifx/main.cf file.