Seemingly bug-free and free (as in freedom) version of Observium's ifAlias snmp extension.

scripts/ifAlias

@@ -0,0 +1,50 @@
+#!/bin/bash
+# (c) 2013, f0o@devilcode.org
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License as published by
+#    the Free Software Foundation, either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU General Public License for more details.
+#
+#    You should have received a copy of the GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+BASE='.1.3.6.1.2.1.31.1.1.1.18'
+ID=$(cut -d . -f 13 <<< $2)
+cache=$(ip l)
+
+if [ -z "$ID" ]; then
+	ID=0
+fi
+
+if [ "$1" = "-n" ]; then
+	IFS="
+"
+	for dev in $(grep mtu <<<"$cache" | cut -d : -f 1|sort -n); do
+		if [ "$LAST" == "$ID" ]; then
+			ID=$dev
+			BRK=1
+			break
+		else
+			LAST=$dev
+		fi
+	done
+	if [ -z "$BRK" ]; then
+		exit 0
+	fi
+fi
+
+IFACE=$(grep "^${ID}: " <<<"$cache" | sed 's/[:@]\s/ /g'| cut -d " " -f 2)
+
+echo ${BASE}.${ID}
+if [ "X${IFACE}" = "X" ]; then
+	echo noSuchName
+else
+	echo "string"
+	echo $(grep "^# $IFACE:" /etc/network/interfaces | sed "s/^# $IFACE: //")
+fi
+exit 0