GrepUpgradeBreaksDevPts - Revision history

Ramuk at 00:32, 11 November 2007

Ramuk — Sun, 11 Nov 2007 00:32:08 GMT

← Older revision		Revision as of 00:32, 11 November 2007
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		+	{{Template:Articles\|Terastation}}
	If you upgrade from the firmware's grep to one of the newer packaged ones floating around, you might find that all of a sudden your telnetd and sshd services don't work. Typical symptoms of the error:		If you upgrade from the firmware's grep to one of the newer packaged ones floating around, you might find that all of a sudden your telnetd and sshd services don't work. Typical symptoms of the error:

Ramuk: 4 revision(s)

Ramuk — Sat, 10 Nov 2007 17:14:30 GMT

4 revision(s)

← Older revision

Revision as of 17:14, 10 November 2007

Aspiers: by the magic of google people will find this

Aspiers — Sun, 01 Jul 2007 17:32:03 GMT

by the magic of google people will find this

← Older revision		Revision as of 17:32, 1 July 2007
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	Jul 1 17:35:49 HD-HTGLD03 sshd[8255]: error: session_pty_req: session 0 alloc failed		Jul 1 17:35:49 HD-HTGLD03 sshd[8255]: error: session_pty_req: session 0 alloc failed
	Jul 1 17:35:49 HD-HTGLD03 sshd[8257]: error: setlogin failed: Function not implemented		Jul 1 17:35:49 HD-HTGLD03 sshd[8257]: error: setlogin failed: Function not implemented
-
-	~~from sshd~~

	This is most likely because devpts isn't being correctly mounted on /dev/pts any more. Let's take a close look at /etc/init.d/devpts.sh:		This is most likely because devpts isn't being correctly mounted on /dev/pts any more. Let's take a close look at /etc/init.d/devpts.sh:

Aspiers at 17:31, 1 July 2007

Aspiers — Sun, 01 Jul 2007 17:31:40 GMT

← Older revision		Revision as of 17:31, 1 July 2007
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-	If you upgrade from the firmware's grep to one of the newer packaged ones floating around, you might find that all of a sudden your telnetd and sshd services don't work. This is most likely because devpts isn't being correctly mounted on /dev/pts any more. Let's take a close look at /etc/init.d/devpts.sh:	+	If you upgrade from the firmware's grep to one of the newer packaged ones floating around, you might find that all of a sudden your telnetd and sshd services don't work. Typical symptoms of the error:
		+
		+	$ telnet tera
		+	Trying 192.168.11.150...
		+	Connected to tera.
		+	Escape character is '^]'.
		+	telnetd: getpty: No such file or directory
		+	.
		+	Connection closed by foreign host.
		+
		+	or
		+
		+	Jul 1 17:35:49 HD-HTGLD03 sshd[8255]: error: openpty: No such file or directory
		+	Jul 1 17:35:49 HD-HTGLD03 sshd[8255]: error: session_pty_req: session 0 alloc failed
		+	Jul 1 17:35:49 HD-HTGLD03 sshd[8257]: error: setlogin failed: Function not implemented
		+
		+	from sshd
		+
		+	This is most likely because devpts isn't being correctly mounted on /dev/pts any more. Let's take a close look at /etc/init.d/devpts.sh:

	devpts_avail=$(grep -qci '[<[:space:]]devpts' /proc/filesystems \|\| true)		devpts_avail=$(grep -qci '[<[:space:]]devpts' /proc/filesystems \|\| true)

Aspiers at 17:23, 1 July 2007

Aspiers — Sun, 01 Jul 2007 17:23:23 GMT

← Older revision		Revision as of 17:23, 1 July 2007
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	Look at the impact of upgrading grep:		Look at the impact of upgrading grep:

-	root@HD-HTGLD03 ~~/etc/init.d~~ # grep devpts /proc/filesystems	+	root@HD-HTGLD03 ~ # grep devpts /proc/filesystems
	nodev devpts		nodev devpts
-	root@HD-HTGLD03 ~~/etc/init.d~~ # ./grep.old -qci devpts /proc/filesystems	+	root@HD-HTGLD03 ~ # ./grep.old -qci devpts /proc/filesystems
	1		1
-	root@HD-HTGLD03 ~~/etc/init.d~~ # grep -qci devpts /proc/filesystems	+	root@HD-HTGLD03 ~ # grep -qci devpts /proc/filesystems
-	root@HD-HTGLD03 ~~/etc/init.d~~ #	+	root@HD-HTGLD03 ~ #

	Oops! The new grep has different behaviour with respect to -qc: it assumes (correctly) that the user does not want any output. This devpts.sh script relies on the dodgy behaviour of the old grep which still issues a match count even when -q is specified.		Oops! The new grep has different behaviour with respect to -qc: it assumes (correctly) that the user does not want any output. This devpts.sh script relies on the dodgy behaviour of the old grep which still issues a match count even when -q is specified.

Aspiers at 17:21, 1 July 2007

Aspiers — Sun, 01 Jul 2007 17:21:57 GMT

New page

If you upgrade from the firmware's grep to one of the newer packaged ones floating around, you might find that all of a sudden your telnetd and sshd services don't work. This is most likely because devpts isn't being correctly mounted on /dev/pts any more. Let's take a close look at /etc/init.d/devpts.sh:

devpts_avail=$(grep -qci '[<[:space:]]devpts' /proc/filesystems || true)
devpts_mounted=$(grep -qci '/dev/pts' /proc/mounts || true)
devfs_mounted=$(grep -qci '[<[:space:]]/dev[>[:space:]].*devfs' /proc/mounts || true)

Look at the impact of upgrading grep:

root@HD-HTGLD03 /etc/init.d # grep devpts /proc/filesystems
nodev devpts
root@HD-HTGLD03 /etc/init.d # ./grep.old -qci devpts /proc/filesystems
1
root@HD-HTGLD03 /etc/init.d # grep -qci devpts /proc/filesystems
root@HD-HTGLD03 /etc/init.d #

Oops! The new grep has different behaviour with respect to -qc: it assumes (correctly) that the user does not want any output. This devpts.sh script relies on the dodgy behaviour of the old grep which still issues a match count even when -q is specified.

The fix is to remove the -q switch from the script:

devpts_avail=$(grep -ci '[<[:space:]]devpts' /proc/filesystems || true)
devpts_mounted=$(grep -ci '/dev/pts' /proc/mounts || true)
devfs_mounted=$(grep -ci '[<[:space:]]/dev[>[:space:]].*devfs' /proc/mounts || true)

--[[User:Aspiers|Aspiers]] 19:21, 1 July 2007 (CEST)