How can I do a loopback test?
Clash Royale CLAN TAG#URR8PPP
Book Computer Networks says
all addresses of the form 127.xx.yy.zz are reserved for loopback
testing. Packets sent to that address are not put out onto the wire; they are processed locally and treated as incoming packets. This allows packets to be sent to
the host without the sender knowing its number, which is useful for testing.
Can you tell me how to do a loopback test in Linux, and contrast it with a non-loopback test which tests the same thing (any thing)? Thanks.
networking loopback
asked Feb 11 at 16:16
TimTim
27.4k78264475
add a comment |
Book Computer Networks says
all addresses of the form 127.xx.yy.zz are reserved for loopback
testing. Packets sent to that address are not put out onto the wire; they are processed locally and treated as incoming packets. This allows packets to be sent to
the host without the sender knowing its number, which is useful for testing.
Can you tell me how to do a loopback test in Linux, and contrast it with a non-loopback test which tests the same thing (any thing)? Thanks.
networking loopback
asked Feb 11 at 16:16
TimTim
27.4k78264475
Could you elaborate on what the text refers to asnumber?
– Jeff Schaller
Feb 11 at 16:33
1
@JeffSchaller by "number" the book means "IP" (likely written before IPv6).
– user1133275
Feb 11 at 17:01
@user1133275 that seems likely, but since Tim has the source material, I wanted to make sure we were speaking the same language.
– Jeff Schaller
Feb 11 at 17:02
add a comment |
Book Computer Networks says
all addresses of the form 127.xx.yy.zz are reserved for loopback
testing. Packets sent to that address are not put out onto the wire; they are processed locally and treated as incoming packets. This allows packets to be sent to
the host without the sender knowing its number, which is useful for testing.
Can you tell me how to do a loopback test in Linux, and contrast it with a non-loopback test which tests the same thing (any thing)? Thanks.
networking loopback
asked Feb 11 at 16:16
TimTim
27.4k78264475
Book Computer Networks says
all addresses of the form 127.xx.yy.zz are reserved for loopback
testing. Packets sent to that address are not put out onto the wire; they are processed locally and treated as incoming packets. This allows packets to be sent to
the host without the sender knowing its number, which is useful for testing.
Can you tell me how to do a loopback test in Linux, and contrast it with a non-loopback test which tests the same thing (any thing)? Thanks.
networking loopback
networking loopback
asked Feb 11 at 16:16
TimTim
27.4k78264475
asked Feb 11 at 16:16
TimTim
27.4k78264475
edited Feb 11 at 16:25
Tim
asked Feb 11 at 16:16
TimTim
27.4k78264475
asked Feb 11 at 16:16
TimTim
27.4k78264475
asked Feb 11 at 16:16
TimTim
27.4k78264475
27.4k78264475
Could you elaborate on what the text refers to asnumber?
– Jeff Schaller
Feb 11 at 16:33
1
@JeffSchaller by "number" the book means "IP" (likely written before IPv6).
– user1133275
Feb 11 at 17:01
@user1133275 that seems likely, but since Tim has the source material, I wanted to make sure we were speaking the same language.
– Jeff Schaller
Feb 11 at 17:02
add a comment |
Could you elaborate on what the text refers to asnumber?
– Jeff Schaller
Feb 11 at 16:33
1
@JeffSchaller by "number" the book means "IP" (likely written before IPv6).
– user1133275
Feb 11 at 17:01
@user1133275 that seems likely, but since Tim has the source material, I wanted to make sure we were speaking the same language.
– Jeff Schaller
Feb 11 at 17:02
Could you elaborate on what the text refers to as
number?– Jeff Schaller
Feb 11 at 16:33
Could you elaborate on what the text refers to as
number?– Jeff Schaller
Feb 11 at 16:33
1
1
@JeffSchaller by "number" the book means "IP" (likely written before IPv6).
– user1133275
Feb 11 at 17:01
@JeffSchaller by "number" the book means "IP" (likely written before IPv6).
– user1133275
Feb 11 at 17:01
@user1133275 that seems likely, but since Tim has the source material, I wanted to make sure we were speaking the same language.
– Jeff Schaller
Feb 11 at 17:02
@user1133275 that seems likely, but since Tim has the source material, I wanted to make sure we were speaking the same language.
– Jeff Schaller
Feb 11 at 17:02
add a comment |
4 Answers
4
active
oldest
votes
Simply configure whichever service you wish to test to a valid IP address within the 127.0.0.0/8 CIDR block. Then attempt to connect to it from the same host at that IP address you selected. If it works, then your loopback test succeeded.
The loopback interface and address space is only significant to network infrastructure; to an application or service an IP in the 127.0.0.0/8 block is just like any other IP address.
The difference between running a service on the loopback interface and on an "actual" network interface is that, as the quote in your question says, loopback traffic never goes out "on the wire", which is to say no data are ever transmitted beyond the host itself.
This means that if you are setting a service up on the loopback range for testing, you must test from the same host. If you want to test connections from another host (so as to test network connectivity) you must instead bind your service to a "wire"-facing interface and address, either directly or indirectly.
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
Without using loopback IP address, how would you do the test instead?
– Tim
Feb 12 at 3:28
1
I don't understand the follow-up question. How would one test a service on a loopback IP without using the loopback IP? That's like asking how to test a radio without.. a radio.
– DopeGhoti
Feb 12 at 15:43
How would one test a service without using the loopback IP?
– Tim
Feb 12 at 15:59
1
This is getting far afield of the original question. Most services have configuration files or parameters or other means of configuring them. If you have a specific question that this answer to the OP at the top of the page is not addressing, please edit your question to clarify the intent of your inquiry.
– DopeGhoti
Feb 12 at 17:16
1
That's really not what I said at all. I'm just saying that your question doesn't really tell us anything about the background knowledge you already have or the context in which you're reading this book. I answered usingtelnetas an example, but I have no idea whether you know what that is. I don't know if the result of telnetting to an HTTP server will mean anything to you. I don't really know if you know what I mean by "host" or "interface". If you do know those things, great, but I had to guess. If you don't, I just sparked a cascade of future questions and that isn't a good way to learn.
– Useless
Feb 13 at 13:31
|
show 4 more comments
tell me how to do a loopback test in Linux
Connect to a service running on the local host via loopback (in this case an HTTP server). If the server is configured to listen on all interfaces, you don't even need to reconfigure it.
$ telnet 127.0.0.1 80
, and contrast it with a non-loopback test which tests the same thing (any thing)?
Connect to the same server from a different host via a real network interface (obviously, since that's the only way to get packets to communicate with a different machine).
$ telnet 192.168.0.100 80
(replace 192... with a real IP address or the network hostname)
answered Feb 12 at 21:12
UselessUseless
3,4281419
add a comment |
Yes, but using 1.1.1.1 introduces a dependency on an existing IP address in Australia. Maybe ping -c 1 google.com?
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
1.1.1.1 is not necessarily in Australia, the IP is not tied to only one server.
– Rui F Ribeiro
Feb 13 at 9:26
add a comment |
Can you tell me how to do a loopback test in Linux
ping -c 1 127.0.0.1
, and contrast it with a non-loopback test which tests the same thing (any thing)?
ping -c 1 1.1.1.1
answered Feb 11 at 16:58
user1133275user1133275
3,570823
3
1.1.1.1 is not a loopback address...
– Rui F Ribeiro
Feb 11 at 18:17
@RuiFRibeiro and?
– user1133275
Feb 12 at 20:26
Perhapsping $(ip addr | grep 'inet ' | grep -v 127.0 | awk ' print $2 ' | cut -d/ -f1)would be more appropriate for the non-loopback test?
– Doug O'Neal
Feb 12 at 20:59
@Doug I originally considered that but I have had incompatibilities with that sort of thing in the past and it over complicates the answer so I decided to leave it out.
– user1133275
Feb 12 at 22:23
add a comment |
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4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
Simply configure whichever service you wish to test to a valid IP address within the 127.0.0.0/8 CIDR block. Then attempt to connect to it from the same host at that IP address you selected. If it works, then your loopback test succeeded.
The loopback interface and address space is only significant to network infrastructure; to an application or service an IP in the 127.0.0.0/8 block is just like any other IP address.
The difference between running a service on the loopback interface and on an "actual" network interface is that, as the quote in your question says, loopback traffic never goes out "on the wire", which is to say no data are ever transmitted beyond the host itself.
This means that if you are setting a service up on the loopback range for testing, you must test from the same host. If you want to test connections from another host (so as to test network connectivity) you must instead bind your service to a "wire"-facing interface and address, either directly or indirectly.
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
Without using loopback IP address, how would you do the test instead?
– Tim
Feb 12 at 3:28
1
I don't understand the follow-up question. How would one test a service on a loopback IP without using the loopback IP? That's like asking how to test a radio without.. a radio.
– DopeGhoti
Feb 12 at 15:43
How would one test a service without using the loopback IP?
– Tim
Feb 12 at 15:59
1
This is getting far afield of the original question. Most services have configuration files or parameters or other means of configuring them. If you have a specific question that this answer to the OP at the top of the page is not addressing, please edit your question to clarify the intent of your inquiry.
– DopeGhoti
Feb 12 at 17:16
1
That's really not what I said at all. I'm just saying that your question doesn't really tell us anything about the background knowledge you already have or the context in which you're reading this book. I answered usingtelnetas an example, but I have no idea whether you know what that is. I don't know if the result of telnetting to an HTTP server will mean anything to you. I don't really know if you know what I mean by "host" or "interface". If you do know those things, great, but I had to guess. If you don't, I just sparked a cascade of future questions and that isn't a good way to learn.
– Useless
Feb 13 at 13:31
|
show 4 more comments
Simply configure whichever service you wish to test to a valid IP address within the 127.0.0.0/8 CIDR block. Then attempt to connect to it from the same host at that IP address you selected. If it works, then your loopback test succeeded.
The loopback interface and address space is only significant to network infrastructure; to an application or service an IP in the 127.0.0.0/8 block is just like any other IP address.
The difference between running a service on the loopback interface and on an "actual" network interface is that, as the quote in your question says, loopback traffic never goes out "on the wire", which is to say no data are ever transmitted beyond the host itself.
This means that if you are setting a service up on the loopback range for testing, you must test from the same host. If you want to test connections from another host (so as to test network connectivity) you must instead bind your service to a "wire"-facing interface and address, either directly or indirectly.
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
Without using loopback IP address, how would you do the test instead?
– Tim
Feb 12 at 3:28
1
I don't understand the follow-up question. How would one test a service on a loopback IP without using the loopback IP? That's like asking how to test a radio without.. a radio.
– DopeGhoti
Feb 12 at 15:43
How would one test a service without using the loopback IP?
– Tim
Feb 12 at 15:59
1
This is getting far afield of the original question. Most services have configuration files or parameters or other means of configuring them. If you have a specific question that this answer to the OP at the top of the page is not addressing, please edit your question to clarify the intent of your inquiry.
– DopeGhoti
Feb 12 at 17:16
1
That's really not what I said at all. I'm just saying that your question doesn't really tell us anything about the background knowledge you already have or the context in which you're reading this book. I answered usingtelnetas an example, but I have no idea whether you know what that is. I don't know if the result of telnetting to an HTTP server will mean anything to you. I don't really know if you know what I mean by "host" or "interface". If you do know those things, great, but I had to guess. If you don't, I just sparked a cascade of future questions and that isn't a good way to learn.
– Useless
Feb 13 at 13:31
|
show 4 more comments
Simply configure whichever service you wish to test to a valid IP address within the 127.0.0.0/8 CIDR block. Then attempt to connect to it from the same host at that IP address you selected. If it works, then your loopback test succeeded.
The loopback interface and address space is only significant to network infrastructure; to an application or service an IP in the 127.0.0.0/8 block is just like any other IP address.
The difference between running a service on the loopback interface and on an "actual" network interface is that, as the quote in your question says, loopback traffic never goes out "on the wire", which is to say no data are ever transmitted beyond the host itself.
This means that if you are setting a service up on the loopback range for testing, you must test from the same host. If you want to test connections from another host (so as to test network connectivity) you must instead bind your service to a "wire"-facing interface and address, either directly or indirectly.
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
Simply configure whichever service you wish to test to a valid IP address within the 127.0.0.0/8 CIDR block. Then attempt to connect to it from the same host at that IP address you selected. If it works, then your loopback test succeeded.
The loopback interface and address space is only significant to network infrastructure; to an application or service an IP in the 127.0.0.0/8 block is just like any other IP address.
The difference between running a service on the loopback interface and on an "actual" network interface is that, as the quote in your question says, loopback traffic never goes out "on the wire", which is to say no data are ever transmitted beyond the host itself.
This means that if you are setting a service up on the loopback range for testing, you must test from the same host. If you want to test connections from another host (so as to test network connectivity) you must instead bind your service to a "wire"-facing interface and address, either directly or indirectly.
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
edited Feb 12 at 17:20
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
answered Feb 11 at 17:05
DopeGhotiDopeGhoti
46k56089
46k56089
Without using loopback IP address, how would you do the test instead?
– Tim
Feb 12 at 3:28
1
I don't understand the follow-up question. How would one test a service on a loopback IP without using the loopback IP? That's like asking how to test a radio without.. a radio.
– DopeGhoti
Feb 12 at 15:43
How would one test a service without using the loopback IP?
– Tim
Feb 12 at 15:59
1
This is getting far afield of the original question. Most services have configuration files or parameters or other means of configuring them. If you have a specific question that this answer to the OP at the top of the page is not addressing, please edit your question to clarify the intent of your inquiry.
– DopeGhoti
Feb 12 at 17:16
1
That's really not what I said at all. I'm just saying that your question doesn't really tell us anything about the background knowledge you already have or the context in which you're reading this book. I answered usingtelnetas an example, but I have no idea whether you know what that is. I don't know if the result of telnetting to an HTTP server will mean anything to you. I don't really know if you know what I mean by "host" or "interface". If you do know those things, great, but I had to guess. If you don't, I just sparked a cascade of future questions and that isn't a good way to learn.
– Useless
Feb 13 at 13:31
|
show 4 more comments
Without using loopback IP address, how would you do the test instead?
– Tim
Feb 12 at 3:28
1
I don't understand the follow-up question. How would one test a service on a loopback IP without using the loopback IP? That's like asking how to test a radio without.. a radio.
– DopeGhoti
Feb 12 at 15:43
How would one test a service without using the loopback IP?
– Tim
Feb 12 at 15:59
1
This is getting far afield of the original question. Most services have configuration files or parameters or other means of configuring them. If you have a specific question that this answer to the OP at the top of the page is not addressing, please edit your question to clarify the intent of your inquiry.
– DopeGhoti
Feb 12 at 17:16
1
That's really not what I said at all. I'm just saying that your question doesn't really tell us anything about the background knowledge you already have or the context in which you're reading this book. I answered usingtelnetas an example, but I have no idea whether you know what that is. I don't know if the result of telnetting to an HTTP server will mean anything to you. I don't really know if you know what I mean by "host" or "interface". If you do know those things, great, but I had to guess. If you don't, I just sparked a cascade of future questions and that isn't a good way to learn.
– Useless
Feb 13 at 13:31
Without using loopback IP address, how would you do the test instead?
– Tim
Feb 12 at 3:28
Without using loopback IP address, how would you do the test instead?
– Tim
Feb 12 at 3:28
1
1
I don't understand the follow-up question. How would one test a service on a loopback IP without using the loopback IP? That's like asking how to test a radio without.. a radio.
– DopeGhoti
Feb 12 at 15:43
I don't understand the follow-up question. How would one test a service on a loopback IP without using the loopback IP? That's like asking how to test a radio without.. a radio.
– DopeGhoti
Feb 12 at 15:43
How would one test a service without using the loopback IP?
– Tim
Feb 12 at 15:59
How would one test a service without using the loopback IP?
– Tim
Feb 12 at 15:59
1
1
This is getting far afield of the original question. Most services have configuration files or parameters or other means of configuring them. If you have a specific question that this answer to the OP at the top of the page is not addressing, please edit your question to clarify the intent of your inquiry.
– DopeGhoti
Feb 12 at 17:16
This is getting far afield of the original question. Most services have configuration files or parameters or other means of configuring them. If you have a specific question that this answer to the OP at the top of the page is not addressing, please edit your question to clarify the intent of your inquiry.
– DopeGhoti
Feb 12 at 17:16
1
1
That's really not what I said at all. I'm just saying that your question doesn't really tell us anything about the background knowledge you already have or the context in which you're reading this book. I answered using
telnet as an example, but I have no idea whether you know what that is. I don't know if the result of telnetting to an HTTP server will mean anything to you. I don't really know if you know what I mean by "host" or "interface". If you do know those things, great, but I had to guess. If you don't, I just sparked a cascade of future questions and that isn't a good way to learn.– Useless
Feb 13 at 13:31
That's really not what I said at all. I'm just saying that your question doesn't really tell us anything about the background knowledge you already have or the context in which you're reading this book. I answered using
telnet as an example, but I have no idea whether you know what that is. I don't know if the result of telnetting to an HTTP server will mean anything to you. I don't really know if you know what I mean by "host" or "interface". If you do know those things, great, but I had to guess. If you don't, I just sparked a cascade of future questions and that isn't a good way to learn.– Useless
Feb 13 at 13:31
|
show 4 more comments
tell me how to do a loopback test in Linux
Connect to a service running on the local host via loopback (in this case an HTTP server). If the server is configured to listen on all interfaces, you don't even need to reconfigure it.
$ telnet 127.0.0.1 80
, and contrast it with a non-loopback test which tests the same thing (any thing)?
Connect to the same server from a different host via a real network interface (obviously, since that's the only way to get packets to communicate with a different machine).
$ telnet 192.168.0.100 80
(replace 192... with a real IP address or the network hostname)
answered Feb 12 at 21:12
UselessUseless
3,4281419
add a comment |
tell me how to do a loopback test in Linux
Connect to a service running on the local host via loopback (in this case an HTTP server). If the server is configured to listen on all interfaces, you don't even need to reconfigure it.
$ telnet 127.0.0.1 80
, and contrast it with a non-loopback test which tests the same thing (any thing)?
Connect to the same server from a different host via a real network interface (obviously, since that's the only way to get packets to communicate with a different machine).
$ telnet 192.168.0.100 80
(replace 192... with a real IP address or the network hostname)
answered Feb 12 at 21:12
UselessUseless
3,4281419
add a comment |
tell me how to do a loopback test in Linux
Connect to a service running on the local host via loopback (in this case an HTTP server). If the server is configured to listen on all interfaces, you don't even need to reconfigure it.
$ telnet 127.0.0.1 80
, and contrast it with a non-loopback test which tests the same thing (any thing)?
Connect to the same server from a different host via a real network interface (obviously, since that's the only way to get packets to communicate with a different machine).
$ telnet 192.168.0.100 80
(replace 192... with a real IP address or the network hostname)
answered Feb 12 at 21:12
UselessUseless
3,4281419
tell me how to do a loopback test in Linux
Connect to a service running on the local host via loopback (in this case an HTTP server). If the server is configured to listen on all interfaces, you don't even need to reconfigure it.
$ telnet 127.0.0.1 80
, and contrast it with a non-loopback test which tests the same thing (any thing)?
Connect to the same server from a different host via a real network interface (obviously, since that's the only way to get packets to communicate with a different machine).
$ telnet 192.168.0.100 80
(replace 192... with a real IP address or the network hostname)
answered Feb 12 at 21:12
UselessUseless
3,4281419
answered Feb 12 at 21:12
UselessUseless
3,4281419
answered Feb 12 at 21:12
UselessUseless
3,4281419
answered Feb 12 at 21:12
UselessUseless
3,4281419
3,4281419
add a comment |
add a comment |
Yes, but using 1.1.1.1 introduces a dependency on an existing IP address in Australia. Maybe ping -c 1 google.com?
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
1.1.1.1 is not necessarily in Australia, the IP is not tied to only one server.
– Rui F Ribeiro
Feb 13 at 9:26
add a comment |
Yes, but using 1.1.1.1 introduces a dependency on an existing IP address in Australia. Maybe ping -c 1 google.com?
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
1.1.1.1 is not necessarily in Australia, the IP is not tied to only one server.
– Rui F Ribeiro
Feb 13 at 9:26
add a comment |
Yes, but using 1.1.1.1 introduces a dependency on an existing IP address in Australia. Maybe ping -c 1 google.com?
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
Yes, but using 1.1.1.1 introduces a dependency on an existing IP address in Australia. Maybe ping -c 1 google.com?
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
answered Feb 12 at 23:27
Doug O'NealDoug O'Neal
2,9501818
2,9501818
1.1.1.1 is not necessarily in Australia, the IP is not tied to only one server.
– Rui F Ribeiro
Feb 13 at 9:26
add a comment |
1.1.1.1 is not necessarily in Australia, the IP is not tied to only one server.
– Rui F Ribeiro
Feb 13 at 9:26
1.1.1.1 is not necessarily in Australia, the IP is not tied to only one server.
– Rui F Ribeiro
Feb 13 at 9:26
1.1.1.1 is not necessarily in Australia, the IP is not tied to only one server.
– Rui F Ribeiro
Feb 13 at 9:26
add a comment |
Can you tell me how to do a loopback test in Linux
ping -c 1 127.0.0.1
, and contrast it with a non-loopback test which tests the same thing (any thing)?
ping -c 1 1.1.1.1
answered Feb 11 at 16:58
user1133275user1133275
3,570823
3
1.1.1.1 is not a loopback address...
– Rui F Ribeiro
Feb 11 at 18:17
@RuiFRibeiro and?
– user1133275
Feb 12 at 20:26
Perhapsping $(ip addr | grep 'inet ' | grep -v 127.0 | awk ' print $2 ' | cut -d/ -f1)would be more appropriate for the non-loopback test?
– Doug O'Neal
Feb 12 at 20:59
@Doug I originally considered that but I have had incompatibilities with that sort of thing in the past and it over complicates the answer so I decided to leave it out.
– user1133275
Feb 12 at 22:23
add a comment |
Can you tell me how to do a loopback test in Linux
ping -c 1 127.0.0.1
, and contrast it with a non-loopback test which tests the same thing (any thing)?
ping -c 1 1.1.1.1
answered Feb 11 at 16:58
user1133275user1133275
3,570823
3
1.1.1.1 is not a loopback address...
– Rui F Ribeiro
Feb 11 at 18:17
@RuiFRibeiro and?
– user1133275
Feb 12 at 20:26
Perhapsping $(ip addr | grep 'inet ' | grep -v 127.0 | awk ' print $2 ' | cut -d/ -f1)would be more appropriate for the non-loopback test?
– Doug O'Neal
Feb 12 at 20:59
@Doug I originally considered that but I have had incompatibilities with that sort of thing in the past and it over complicates the answer so I decided to leave it out.
– user1133275
Feb 12 at 22:23
add a comment |
Can you tell me how to do a loopback test in Linux
ping -c 1 127.0.0.1
, and contrast it with a non-loopback test which tests the same thing (any thing)?
ping -c 1 1.1.1.1
answered Feb 11 at 16:58
user1133275user1133275
3,570823
Can you tell me how to do a loopback test in Linux
ping -c 1 127.0.0.1
, and contrast it with a non-loopback test which tests the same thing (any thing)?
ping -c 1 1.1.1.1
answered Feb 11 at 16:58
user1133275user1133275
3,570823
edited Feb 12 at 20:26
answered Feb 11 at 16:58
user1133275user1133275
3,570823
answered Feb 11 at 16:58
user1133275user1133275
3,570823
answered Feb 11 at 16:58
user1133275user1133275
3,570823
3,570823
3
1.1.1.1 is not a loopback address...
– Rui F Ribeiro
Feb 11 at 18:17
@RuiFRibeiro and?
– user1133275
Feb 12 at 20:26
Perhapsping $(ip addr | grep 'inet ' | grep -v 127.0 | awk ' print $2 ' | cut -d/ -f1)would be more appropriate for the non-loopback test?
– Doug O'Neal
Feb 12 at 20:59
@Doug I originally considered that but I have had incompatibilities with that sort of thing in the past and it over complicates the answer so I decided to leave it out.
– user1133275
Feb 12 at 22:23
add a comment |
3
1.1.1.1 is not a loopback address...
– Rui F Ribeiro
Feb 11 at 18:17
@RuiFRibeiro and?
– user1133275
Feb 12 at 20:26
Perhapsping $(ip addr | grep 'inet ' | grep -v 127.0 | awk ' print $2 ' | cut -d/ -f1)would be more appropriate for the non-loopback test?
– Doug O'Neal
Feb 12 at 20:59
@Doug I originally considered that but I have had incompatibilities with that sort of thing in the past and it over complicates the answer so I decided to leave it out.
– user1133275
Feb 12 at 22:23
3
3
1.1.1.1 is not a loopback address...
– Rui F Ribeiro
Feb 11 at 18:17
1.1.1.1 is not a loopback address...
– Rui F Ribeiro
Feb 11 at 18:17
@RuiFRibeiro and?
– user1133275
Feb 12 at 20:26
@RuiFRibeiro and?
– user1133275
Feb 12 at 20:26
Perhaps
ping $(ip addr | grep 'inet ' | grep -v 127.0 | awk ' print $2 ' | cut -d/ -f1) would be more appropriate for the non-loopback test?– Doug O'Neal
Feb 12 at 20:59
Perhaps
ping $(ip addr | grep 'inet ' | grep -v 127.0 | awk ' print $2 ' | cut -d/ -f1) would be more appropriate for the non-loopback test?– Doug O'Neal
Feb 12 at 20:59
@Doug I originally considered that but I have had incompatibilities with that sort of thing in the past and it over complicates the answer so I decided to leave it out.
– user1133275
Feb 12 at 22:23
@Doug I originally considered that but I have had incompatibilities with that sort of thing in the past and it over complicates the answer so I decided to leave it out.
– user1133275
Feb 12 at 22:23
add a comment |
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Could you elaborate on what the text refers to as
number?– Jeff Schaller
Feb 11 at 16:33
1
@JeffSchaller by "number" the book means "IP" (likely written before IPv6).
– user1133275
Feb 11 at 17:01
@user1133275 that seems likely, but since Tim has the source material, I wanted to make sure we were speaking the same language.
– Jeff Schaller
Feb 11 at 17:02