Operating Systems 2017F: Assignment 4 - Revision history

Soma: /* Multiple Choice */

2017-12-07T18:18:36Z

Multiple Choice

← Older revision		Revision as of 18:18, 7 December 2017
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	<li> In sshfs, do a file's uid and gid values come from the remote server or from the mounting user's uid and gid?		<li> In sshfs, do a file's uid and gid values come from the remote server or from the mounting user's uid and gid?
	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li>From the remote server.		<li>'''From the remote server.'''
	<li>From the mounting user's uid and gid.		<li>From the mounting user's uid and gid.
	</ol>		</ol>
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	<li>Process's gid matches the file's gid.		<li>Process's gid matches the file's gid.
	<li>The process's uid and gid match the file's uid and gid.		<li>The process's uid and gid match the file's uid and gid.
	<li>None of the above.		<li>'''None of the above.'''
	</ol>		</ol>
	<li> In sshfs, what determines whether a file operation is allowed or not?		<li> In sshfs, what determines whether a file operation is allowed or not?
	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li>the remote ssh daemon		<li>the remote ssh daemon
	<li>the remote kernel		<li>'''the remote kernel'''
	<li>the local kernel		<li>the local kernel
	<li>the local ssh process		<li>the local ssh process
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	<li>euid is equal to the uid of the calling user (process that did the execve of fusermount)		<li>euid is equal to the uid of the calling user (process that did the execve of fusermount)
	<li>euid is the uid of fuse		<li>euid is the uid of fuse
	<li>euid=0 (root)		<li>'''euid=0 (root)'''
	<li>None of the above		<li>None of the above
	</ol>		</ol>
	<li> What environment variable allows ssh to connect to the local authentication agent?		<li> What environment variable allows ssh to connect to the local authentication agent?
	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li>SSH_AUTH_SOCK		<li>'''SSH_AUTH_SOCK'''
	<li>TERM		<li>TERM
	<li>SSH_AGENT_LAUNCHER		<li>SSH_AGENT_LAUNCHER
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	<li>Other regular users on the system could use the private key to impersonate the owner.		<li>Other regular users on the system could use the private key to impersonate the owner.
	<li>ssh and ssh-add will refuse to use the key.		<li>ssh and ssh-add will refuse to use the key.
	<li>Both (a) and (b)		<li>'''Both (a) and (b)'''
	<li>None of the above		<li>None of the above
	</ol>		</ol>
	<li> What option to you give to dd to control how many bytes dd writes with each write system call?		<li> What option to you give to dd to control how many bytes dd writes with each write system call?
	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li>bs=		<li>'''bs='''
	<li>ibs=		<li>ibs=
	<li>count=		<li>count=
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	<li> When you make a write system call to a file on a sshfs-mounted filesystem (to a file that the user has write access to) , which of the following also happens?		<li> When you make a write system call to a file on a sshfs-mounted filesystem (to a file that the user has write access to) , which of the following also happens?
	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li>A remote sftp-server process does a write system call.		<li>'''A remote sftp-server process does a write system call.'''
	<li>The local kernel makes a write system call.		<li>The local kernel makes a write system call.
	<li>The remote kernel makes a write system call.		<li>The remote kernel makes a write system call.

Soma: /* Multiple Choice */

2017-12-07T18:16:10Z

Multiple Choice

← Older revision		Revision as of 18:16, 7 December 2017
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	<li>Line 14, <tt>self.ino += 1</tt>		<li>Line 14, <tt>self.ino += 1</tt>
	<li>Line 18, <tt>self.ino = 1</tt>		<li>Line 18, <tt>self.ino = 1</tt>
	<li>Both Line 14 and 18		<li>'''Both Line 14 and 18'''
	<li>None of the above		<li>None of the above
	</ol>		</ol>

Soma: /* Multiple Choice */

2017-12-07T18:14:45Z

Multiple Choice

← Older revision		Revision as of 18:14, 7 December 2017
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	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li> The sshfs inode values are identical to those on the remote filesystem.		<li> The sshfs inode values are identical to those on the remote filesystem.
	<li> The sshfs inode values have no relationship to the remote filesystem inode values.		<li> '''The sshfs inode values have no relationship to the remote filesystem inode values.'''
	<li> The sshfs inode values are the remote inode numbers plus a fixed offset.		<li> The sshfs inode values are the remote inode numbers plus a fixed offset.
	<li> The sshfs inode values are sometimes the same as the remote inode values, and sometimes they are different.		<li> The sshfs inode values are sometimes the same as the remote inode values, and sometimes they are different.

Soma: /* Multiple Choice */

2017-12-07T18:12:39Z

Multiple Choice

← Older revision		Revision as of 18:12, 7 December 2017
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	<li> ~/.ssh/known_hosts		<li> ~/.ssh/known_hosts
	<li> ~/.ssh/id_rsa.pub		<li> ~/.ssh/id_rsa.pub
	<li> ~/.ssh/id_rsa		<li> '''~/.ssh/id_rsa'''
	</ol>		</ol>
	<li> How do sshfs inode values relate to the inodes in the remotely mounted filesystem?		<li> How do sshfs inode values relate to the inodes in the remotely mounted filesystem?

Soma: /* Multiple Choice */

2017-12-07T18:12:01Z

Multiple Choice

← Older revision		Revision as of 18:12, 7 December 2017
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	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li> /etc/passwd		<li> /etc/passwd
	<li> ~/.ssh/authorized_keys		<li> '''~/.ssh/authorized_keys'''
	<li> ~/.ssh/known_hosts		<li> ~/.ssh/known_hosts
	<li> ~/.ssh/id_rsa.pub		<li> ~/.ssh/id_rsa.pub

Soma at 16:40, 4 December 2017

2017-12-04T16:40:12Z

← Older revision		Revision as of 16:40, 4 December 2017
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	These questions refer to the code from [[Operating Systems 2017F: Tutorial 7\|Tutorial 7]] and [[Operating Systems 2017F: Tutorial 7\|Tutorial 8]].		These questions refer to the code from [[Operating Systems 2017F: Tutorial 7\|Tutorial 7]] and [[Operating Systems 2017F: Tutorial 8\|Tutorial 8]].

	==Full Questions==		==Full Questions==

Soma at 16:39, 4 December 2017

2017-12-04T16:39:53Z

← Older revision		Revision as of 16:39, 4 December 2017
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			These questions refer to the code from [[Operating Systems 2017F: Tutorial 7\|Tutorial 7]] and [[Operating Systems 2017F: Tutorial 7\|Tutorial 8]].

	==Full Questions==		==Full Questions==

Soma at 02:44, 4 December 2017

2017-12-04T02:44:13Z

← Older revision		Revision as of 02:44, 4 December 2017
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	~~'''This assignment is not yet finalized.'''~~

	==Full Questions==		==Full Questions==

Soma: /* Multiple Choice */

2017-12-03T23:02:38Z

Multiple Choice

← Older revision		Revision as of 23:02, 3 December 2017
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	<li>None of the above		<li>None of the above
	</ol>		</ol>
	<li> ~~How do~~ you control how many bytes dd writes with each write system call?		<li> What option to you give to dd to control how many bytes dd writes with each write system call?
	<ol style="list-style-type:lower-alpha">		<ol style="list-style-type:lower-alpha">
	<li>bs=		<li>bs=

Soma: /* Multiple Choice */

2017-12-03T23:02:04Z

Multiple Choice

← Older revision		Revision as of 23:02, 3 December 2017
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	<li>None of the above		<li>None of the above
	</ol>		</ol>
	<li> When you make a write system call to a file on a sshfs-mounted filesystem, ~~how many additional~~ write ~~(or writev)~~ system ~~calls must be executed, and what processes make those~~ system ~~calls?~~		<li> When you make a write system call to a file on a sshfs-mounted filesystem (to a file that the user has write access to) , which of the following also happens?
			<ol style="list-style-type:lower-alpha">
			<li>A remote sftp-server process does a write system call.
			<li>The local kernel makes a write system call.
			<li>The remote kernel makes a write system call.
			<li>All of the above.
			</ol>
	</ol>		</ol>