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Q1: So smtp is not running, correct?
Services should show up on systemctl. No?
But on netstat, it shows smtp is running:
Code:
student@localhost ~]$ netstat -taupe | grep smtp
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
tcp 0 0 localhost:smtp 0.0.0.0:* LISTEN root 24224 -
tcp6 0 0 localhost:smtp [::]:* LISTEN root 24225 -
Looks like localhost has smtp running on all ports, 0.0.0.0:* .
Q2: So why is smtp not showing up on command output like so:
Code:
systemctl status | grep -i smtp
Since smtp is on localhost,
I should be able to telnet into localhost like so:
Code:
[student@localhost ~]$ telnet localhost 25
Trying ::1...
Connected to localhost.
Escape character is '^]'.
220 localhost.localdomain ESMTP Postfix
#Not getting a telnet prompt, "telnet>".
BUT netstat shows I am connected like so:
(Shown on last line for user, student. )
Code:
[student@localhost ~]$ netstat -taupe | grep smtp
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
tcp 0 0 localhost:smtp 0.0.0.0:* LISTEN root 24224 -
tcp6 0 0 localhost:smtp [::]:* LISTEN root 24225 -
tcp6 0 0 localhost:smtp localhost:56974 ESTABLISHED postfix 59454 -
tcp6 0 0 localhost:56974 localhost:smtp ESTABLISHED student 59295 5677/telnet
SMTP i.e Simple Mail Transfer Protocol is not a service. It is how some mail clients/servers talk to each other. The service that is running is postfix which by default runs on port 25. Since SMTP is ASCII you can use telnet to communicate with the postfix server but it isn't like a regular terminal session.
The telnet protocol works like a terminal program for human interaction to a remote computer but SMTP is not. Since it does not work the same there isn't a prompt.
virbr0 is acting as a NAT router and I would guess that the host services are not listening on the virtual interface. If you want to access the host services from the guest you might need to configure it as a bridge.
virbr0 is acting as a NAT router and I would guess that the host services are not listening on the virtual interface. If you want to access the host services from the guest you might need to configure it as a bridge.
I have rebooted the laptop.
thus the VM's IP has changed.
Here is the VM's network setup:
Code:
[student@localhost ~]$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:e1:93:0b brd ff:ff:ff:ff:ff:ff
inet 10.0.0.145/24 brd 10.0.0.255 scope global dynamic eno16777736
valid_lft 604657sec preferred_lft 604657sec
inet6 fe80::20c:29ff:fee1:930b/64 scope link
valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN
link/ether 52:54:00:ae:4d:5c brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN qlen 500
link/ether 52:54:00:ae:4d:5c brd ff:ff:ff:ff:ff:ff
Notice virtual bridge, virbr0, is DOWN.
And here is what I tried with no success, meaning virtual bridge's state is still DOWN:
Code:
[student@localhost ~]$ sudo ip link set virbr0 up
[student@localhost ~]$ sudo ip link show virbr0
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT
link/ether 52:54:00:ae:4d:5c brd ff:ff:ff:ff:ff:ff
I look into nmtui, and I am not sure what to do next to enable virbr0.
virbr0 is already in nmtui.
There is no provision to turn it on in nmtui.
Here is the screen shot from VMware's setup:
(There is no add image icon button in menu area for me to insert image here!
But I was able to attach it to this post.)
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