SSH connection getting closed automatically after a sudo command
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I have two servers running the same version of RedHat 6.4, however one of them behaves differently when I run remote sudo commands through SSH on it. On server1, the connection is automatically closed after a successful sudo command, but on server3, the connection is kept open.
Note that for these tests the sudo user had the NOPASSWD flag so no prompt is asked. As far as I know, all configurations on these servers are the same (they were cloned).
I tested using this:
ssh -vvv user@server1 << EOF
sudo ls -l /home/
ls -l /home/
pwd
EOF
If I run this on server1 I get a single file listing.
debug3: Wrote 32 bytes for a total of 1621
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
Running without the sudo command on the same server I get my two file listing and the pwd result
ssh -vvv user@server1 << EOF
ls -l /home/
ls -l /home/
pwd
EOF
Result:
debug3: Wrote 32 bytes for a total of 1605
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
/home/user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
However, running the script with the sudo command on server3 I get the result of all 3 commands like the previous test. I compared the output of the ssh -vvv logs from both servers (1 and 3) and everything seems the same except for a debug line in a different order when the connection is closed (see client_input... line).
server1 (same with or without sudo)
[command results]
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug2: channel 0: rcvd close
server3
[command results]
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd close
I would like to know how to fix server1 so that the connection isn't automatically closed so that my script can execute completely when including sudo commands.
ssh rhel sudo
edited yesterday
Rui F Ribeiro
38.7k1479128
asked yesterday
Bibz
1209
add a comment |
up vote
0
down vote
favorite
I have two servers running the same version of RedHat 6.4, however one of them behaves differently when I run remote sudo commands through SSH on it. On server1, the connection is automatically closed after a successful sudo command, but on server3, the connection is kept open.
Note that for these tests the sudo user had the NOPASSWD flag so no prompt is asked. As far as I know, all configurations on these servers are the same (they were cloned).
I tested using this:
ssh -vvv user@server1 << EOF
sudo ls -l /home/
ls -l /home/
pwd
EOF
If I run this on server1 I get a single file listing.
debug3: Wrote 32 bytes for a total of 1621
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
Running without the sudo command on the same server I get my two file listing and the pwd result
ssh -vvv user@server1 << EOF
ls -l /home/
ls -l /home/
pwd
EOF
Result:
debug3: Wrote 32 bytes for a total of 1605
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
/home/user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
However, running the script with the sudo command on server3 I get the result of all 3 commands like the previous test. I compared the output of the ssh -vvv logs from both servers (1 and 3) and everything seems the same except for a debug line in a different order when the connection is closed (see client_input... line).
server1 (same with or without sudo)
[command results]
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug2: channel 0: rcvd close
server3
[command results]
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd close
I would like to know how to fix server1 so that the connection isn't automatically closed so that my script can execute completely when including sudo commands.
ssh rhel sudo
edited yesterday
Rui F Ribeiro
38.7k1479128
asked yesterday
Bibz
1209
I wonder if errexit is being set?
– Jeff Schaller
yesterday
1
also, compare the/etc/sudoersfiles (including/etc/sudoers.d/*), keeping an eye out for anyrequirettyor!requirettydifferences. Perhaps server3 has been configured to allow sudo without requiring atty, and server1 has not. One way to test would be to modify the server 1 command fromssh -vvv user@server1 ...tossh -t -vvv user@server1.... The-toption will force the allocation of a tty. If sudo works doing that, then it's a tty requirement stuffing you up.
– Tim Kennedy
yesterday
errexit is off (command is successful anyway).requirettyis commented out in the sudoers file andsudoers.ddirectory is empty.
– Bibz
yesterday
add a comment |
up vote
0
down vote
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up vote
0
down vote
favorite
I have two servers running the same version of RedHat 6.4, however one of them behaves differently when I run remote sudo commands through SSH on it. On server1, the connection is automatically closed after a successful sudo command, but on server3, the connection is kept open.
Note that for these tests the sudo user had the NOPASSWD flag so no prompt is asked. As far as I know, all configurations on these servers are the same (they were cloned).
I tested using this:
ssh -vvv user@server1 << EOF
sudo ls -l /home/
ls -l /home/
pwd
EOF
If I run this on server1 I get a single file listing.
debug3: Wrote 32 bytes for a total of 1621
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
Running without the sudo command on the same server I get my two file listing and the pwd result
ssh -vvv user@server1 << EOF
ls -l /home/
ls -l /home/
pwd
EOF
Result:
debug3: Wrote 32 bytes for a total of 1605
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
/home/user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
However, running the script with the sudo command on server3 I get the result of all 3 commands like the previous test. I compared the output of the ssh -vvv logs from both servers (1 and 3) and everything seems the same except for a debug line in a different order when the connection is closed (see client_input... line).
server1 (same with or without sudo)
[command results]
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug2: channel 0: rcvd close
server3
[command results]
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd close
I would like to know how to fix server1 so that the connection isn't automatically closed so that my script can execute completely when including sudo commands.
ssh rhel sudo
edited yesterday
Rui F Ribeiro
38.7k1479128
asked yesterday
Bibz
1209
I have two servers running the same version of RedHat 6.4, however one of them behaves differently when I run remote sudo commands through SSH on it. On server1, the connection is automatically closed after a successful sudo command, but on server3, the connection is kept open.
Note that for these tests the sudo user had the NOPASSWD flag so no prompt is asked. As far as I know, all configurations on these servers are the same (they were cloned).
I tested using this:
ssh -vvv user@server1 << EOF
sudo ls -l /home/
ls -l /home/
pwd
EOF
If I run this on server1 I get a single file listing.
debug3: Wrote 32 bytes for a total of 1621
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
Running without the sudo command on the same server I get my two file listing and the pwd result
ssh -vvv user@server1 << EOF
ls -l /home/
ls -l /home/
pwd
EOF
Result:
debug3: Wrote 32 bytes for a total of 1605
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
total 40
drwxr-xr-x. 5 user user 4096 Apr 26 2013 user
/home/user
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
However, running the script with the sudo command on server3 I get the result of all 3 commands like the previous test. I compared the output of the ssh -vvv logs from both servers (1 and 3) and everything seems the same except for a debug line in a different order when the connection is closed (see client_input... line).
server1 (same with or without sudo)
[command results]
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug2: channel 0: rcvd close
server3
[command results]
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd close
I would like to know how to fix server1 so that the connection isn't automatically closed so that my script can execute completely when including sudo commands.
ssh rhel sudo
ssh rhel sudo
edited yesterday
Rui F Ribeiro
38.7k1479128
asked yesterday
Bibz
1209
edited yesterday
Rui F Ribeiro
38.7k1479128
asked yesterday
Bibz
1209
edited yesterday
Rui F Ribeiro
38.7k1479128
edited yesterday
Rui F Ribeiro
38.7k1479128
edited yesterday
Rui F Ribeiro
38.7k1479128
38.7k1479128
asked yesterday
Bibz
1209
asked yesterday
Bibz
1209
asked yesterday
Bibz
1209
1209
I wonder if errexit is being set?
– Jeff Schaller
yesterday
1
also, compare the/etc/sudoersfiles (including/etc/sudoers.d/*), keeping an eye out for anyrequirettyor!requirettydifferences. Perhaps server3 has been configured to allow sudo without requiring atty, and server1 has not. One way to test would be to modify the server 1 command fromssh -vvv user@server1 ...tossh -t -vvv user@server1.... The-toption will force the allocation of a tty. If sudo works doing that, then it's a tty requirement stuffing you up.
– Tim Kennedy
yesterday
errexit is off (command is successful anyway).requirettyis commented out in the sudoers file andsudoers.ddirectory is empty.
– Bibz
yesterday
add a comment |
I wonder if errexit is being set?
– Jeff Schaller
yesterday
1
also, compare the/etc/sudoersfiles (including/etc/sudoers.d/*), keeping an eye out for anyrequirettyor!requirettydifferences. Perhaps server3 has been configured to allow sudo without requiring atty, and server1 has not. One way to test would be to modify the server 1 command fromssh -vvv user@server1 ...tossh -t -vvv user@server1.... The-toption will force the allocation of a tty. If sudo works doing that, then it's a tty requirement stuffing you up.
– Tim Kennedy
yesterday
errexit is off (command is successful anyway).requirettyis commented out in the sudoers file andsudoers.ddirectory is empty.
– Bibz
yesterday
I wonder if errexit is being set?
– Jeff Schaller
yesterday
I wonder if errexit is being set?
– Jeff Schaller
yesterday
1
1
also, compare the
/etc/sudoers files (including /etc/sudoers.d/*), keeping an eye out for any requiretty or !requiretty differences. Perhaps server3 has been configured to allow sudo without requiring a tty, and server1 has not. One way to test would be to modify the server 1 command from ssh -vvv user@server1 ... to ssh -t -vvv user@server1.... The -t option will force the allocation of a tty. If sudo works doing that, then it's a tty requirement stuffing you up.– Tim Kennedy
yesterday
also, compare the
/etc/sudoers files (including /etc/sudoers.d/*), keeping an eye out for any requiretty or !requiretty differences. Perhaps server3 has been configured to allow sudo without requiring a tty, and server1 has not. One way to test would be to modify the server 1 command from ssh -vvv user@server1 ... to ssh -t -vvv user@server1.... The -t option will force the allocation of a tty. If sudo works doing that, then it's a tty requirement stuffing you up.– Tim Kennedy
yesterday
errexit is off (command is successful anyway).
requiretty is commented out in the sudoers file and sudoers.d directory is empty.– Bibz
yesterday
errexit is off (command is successful anyway).
requiretty is commented out in the sudoers file and sudoers.d directory is empty.– Bibz
yesterday
add a comment |
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I wonder if errexit is being set?
– Jeff Schaller
yesterday
1
also, compare the
/etc/sudoersfiles (including/etc/sudoers.d/*), keeping an eye out for anyrequirettyor!requirettydifferences. Perhaps server3 has been configured to allow sudo without requiring atty, and server1 has not. One way to test would be to modify the server 1 command fromssh -vvv user@server1 ...tossh -t -vvv user@server1.... The-toption will force the allocation of a tty. If sudo works doing that, then it's a tty requirement stuffing you up.– Tim Kennedy
yesterday
errexit is off (command is successful anyway).
requirettyis commented out in the sudoers file andsudoers.ddirectory is empty.– Bibz
yesterday